They’re required to use a turbo that’s a specific size (72 mm). Since the turbo limits how much air the engine can breathe, the race becomes about tuning the engine to work best with that exact turbo.
A turbocharger is a device that uses the engine’s exhaust to force more air into the engine. More air helps the engine make more power, especially on a diesel where fuel and air have to be matched.
An intercooler cools the hot, compressed air from the turbo before it goes into the engine. Cooling it helps the engine breathe better and can improve power.
This is an intercooler that uses water to cool the turbo’s compressed air. The rules here don’t allow it because teams could use the water to get extra cooling tricks.
Water-methanol injection is a trick where a liquid mix is sprayed into the engine to cool things down and help it make more power. This race bans it, so everyone has to stay within the fuel-only rules.
Making the biggest peak horsepower number isn’t always what wins. What matters is how well the engine pulls where you spend time during the race, not just the top number on a dyno sheet.
A chassis dyno is a machine that tests a car while it’s sitting still on rollers. It helps show how much power the engine makes and how that power changes as the speed increases.
Concept
power vs winning
The host is arguing that the highest peak power doesn’t automatically translate into race wins. In drag-style racing, traction, torque delivery, and how the truck accelerates across the track can matter as much as (or more than) maximum dyno numbers.
A dyno appearance is when someone brings their truck to a dyno shop to run it on the power-testing machine, sometimes in front of others. People use those results to compare different builds.
Cylinder heads are part of the engine that sit on top of the cylinders and help control how the air and fuel burn. Modifying them can help the engine make more power.
A stock cam is the camshaft that comes from the factory. It’s designed for everyday use, not peak race power, so when racers say “stock cam,” they mean using near-factory valve timing instead of an aggressive aftermarket cam.
Intake duration tells you how long the engine’s intake valves stay open each cycle. If they stay open longer, the engine can breathe better at higher RPM, but it may feel weaker at low RPM.
Exhaust duration is how long the exhaust valves stay open. Longer duration can help the engine clear out exhaust gases at higher speeds, but it can make the engine less responsive at low speeds if the rest of the setup isn’t matched.
The Dodge Charger is a car built for performance, with a powerful engine and a sporty design. People talk about it a lot because it’s popular for upgrades and driving fast. If someone says “get your charger going,” they’re usually referring to starting and using that performance setup.
The “mile per hour” is the car’s speed measured at the end of the run. If two cars are similar in weight and wind, the faster one usually has more effective power.
On an automatic, the torque converter can be locked or unlocked. When it’s unlocked, there’s more “slip,” so the drivetrain is less efficient—especially right after launch.
When the torque converter is locked, the drivetrain connects more directly. That usually makes the car more efficient at turning engine power into acceleration.
“Time under power” means how long the car is actually being pushed forward by the engine’s torque. Longer effective push can help the car build more speed by the end of the run.
“Impulse” is a physics quantity equal to force applied over time (often discussed as the area under the force-vs-time curve). In drag racing terms, higher average impulse from the drivetrain can mean more speed gained over the run.
“Overlap” is when the intake and exhaust valves are open at the same time near the top of the exhaust stroke. More overlap can increase cylinder scavenging and flow, but in turbo-limited applications it can also bleed boost pressure and reduce the usable charge.
“Boost pressure ratio” is the relationship between the boosted intake pressure and the baseline (often atmospheric) pressure. It matters because it affects how much air mass the engine can ingest, which then influences how much fuel can be burned for power.
A “turbo limited application” is a setup where the turbocharger’s ability to make and sustain boost is the main constraint on power. In that case, losing boost (for example via excessive valve overlap) directly hurts the power you can actually use.
The Cadillac CTS V is a high-performance Cadillac. Here it’s used as an example of a supercharged car where the cam timing matters for keeping boost and making strong speed.
Whipple is a company that makes superchargers for performance cars. The host is using it as an example of a bigger supercharger setup that changes how the engine breathes.
Pumping losses are the “work” the engine has to do just to move air in and out. If that work is reduced, the engine can make more of its power for actually turning the wheels.
Scavenging is how effectively the engine clears out old exhaust gases and brings in fresh air. Better scavenging can improve power, especially with the right valve timing.
“Air limited” means the engine can’t get enough air in to take full advantage of the power potential. When that happens, changes that normally help breathing can actually make things worse.
Average power is how much power the engine makes over the range of RPMs you actually use while driving/racing. The host’s point is that being strong across the usable range beats having one big peak number.
An RPM window is the range of engine speeds you’re mostly using while racing. The host is saying the car that performs best in that range tends to win, even if another setup has a higher peak number.
A peak number is the highest value something hits at one moment. The host is saying that racing is about how the car pulls over the whole run, not just the single highest reading.
“Area under the curve” means the total amount of flow over the whole range, not just the highest peak. A head can have a lower top number but still be better if it flows more across the lifts that matter.
Torque is the engine’s pulling force that makes the truck accelerate. On a dyno, it’s measured as a number across different engine speeds, and more torque usually helps you get moving faster—especially when you start from a stop.
Term
stock 67 block
The engine block is the main part of the engine that holds the cylinders. “Stock” here means it wasn’t heavily modified, so the builder relied on other upgrades to make the truck fast.
“Common rail” is how many modern diesels inject fuel. Fuel is kept under high pressure in a shared line, then sent to the engine’s injectors at the right moments. That precision helps the engine make more power and run more smoothly.
Here, “forge” means using forged pistons—pistons made to be extra strong. Stronger pistons can handle more cylinder pressure. But the host is saying that for their target power, factory pistons might work well enough.
Piston wall clearance is the small gap between the moving piston and the inside of the cylinder. It’s there so the piston can expand when it gets hot without rubbing or getting stuck. The right clearance helps prevent damage under high stress.
High compression means the engine squeezes the fuel-air mixture more than usual. That can help make more power, but it also makes the engine run hotter and harder. So it usually needs the right parts and tuning to stay safe.
A deck plate is an engine part used in some builds to change how the cylinder head and piston work together. That can affect compression and combustion. People use it when they’re trying to make more power, but it also changes how hard the engine has to work.
A “big cam” is a camshaft designed to open the engine’s valves more aggressively. That can help the engine breathe better and make more power. But it can also make the engine harder to tune and more stressful on components.
Valve relief pistons have small cutouts in the piston to give extra space for the valves. That prevents the valves from hitting the piston when the engine is modified for more lift or different timing. It’s a safety-and-compatibility upgrade for performance builds.
Atomize means to turn fuel into a fine mist. A good mist mixes with air better and burns more completely. If the fuel isn’t atomized well, you don’t get as much power and it can burn less efficiently.
Top Fuel is a drag-racing category where cars run extremely hard for very short bursts. The host is talking about how those engines are built to survive the abuse, even if the airflow “ports” aren’t perfect by normal performance standards.
Ports are the internal passages in the engine head that help air and fuel get into the cylinders (and exhaust get out). Better ports can improve flow, but the host is saying some top-fuel setups prioritize surviving the race over chasing perfect flow numbers.
“Small block Mopar” is a type of Chrysler V8 engine people build for racing. It’s known for being a common starting point when you want to make big power and tune airflow.
A “horsepower recipe” means the exact way you build and tune an engine to hit a power target. In racing, it’s not just about making the most power once—it’s about not breaking while you’re pushing it hard repeatedly.
“Valve reliefs” are small cutouts inside the piston so the valves have extra space. That helps prevent the valves from hitting the piston when the engine spins fast.
“Valve release” is about how the engine’s valves move at high RPM. The key idea is making sure the valves have enough clearance so they don’t hit the piston.
The Chevrolet Spin is a family-oriented vehicle that’s designed to carry people and cargo. If the podcast is talking about RPM and valve work, they’re referring to the engine’s internal parts and how it runs at different speeds. That’s the kind of topic you’d hear when someone explains engine maintenance or modifications.
“Swirl” is how the air spins inside the engine’s combustion chamber. Better swirl helps the fuel mix and burn cleanly, and changing piston/valve geometry can reduce that benefit.
Fuel injectors spray fuel into the engine. “Flux injectors” are a particular injector type, and the point here is that changing injector nozzle design can change how much power the engine makes.
Diesel injectors spray fuel into the engine. A “six-hole nozzle” means the injector tip has six tiny spray openings, which helps control how the fuel mist is shaped and where it goes.
Short shifting means shifting gears sooner instead of letting the engine rev higher. The idea is to keep the engine in the range where it makes the most useful pull.
Airflow is how much air the engine can pull in. Diesel engines need enough air to burn the fuel cleanly and make power, so the “right” airflow for the RPM range is key.
Valves open and close at specific times in the engine cycle. Cam timing controls when air and exhaust move in and out, and that timing can strongly affect how much power you make at different RPMs.
A camshaft controls when the engine’s valves open and how long they stay open. The episode is saying that the exact timing details matter a lot for power, not just the simple cam specs people quote.
It’s the exact moment the engine’s intake valve shuts. That timing decides how much air the cylinder actually traps before it starts burning fuel, which is a big part of how much power you get.
The Challenger is a muscle car made for strong acceleration and performance. Different versions can have different engines, and those engines can behave a bit differently. When someone mentions a “Hellcat engine,” they’re talking about one of the Challenger’s high-performance engine options.
“12 valve” means the engine has 12 valves in total. More valves can change how the engine breathes, so the timing for when they open and close can be tuned for easier cold starts.
A supercharger is a device that forces more air into the engine. More air (and denser air) can help the engine fill its cylinders better, especially when valve timing and RPM are involved.
Bottom dead center is the point in the engine cycle where the piston is as low as it gets. It matters because the timing of the intake valve near that point can decide whether the engine keeps the air charge or loses it back out.
Cold starting is when you start the engine while it’s been sitting and is cold. Engines often need special valve timing or fueling strategies so they can start and run smoothly until things warm up.
Term
dynamic compression
Dynamic compression is the “real” squeeze the engine gets after you account for when the valves open and close. If the intake valve is open too long, the engine can lose some of the air/fuel charge and make less power.
Compression ratio is how much the engine squeezes the air/fuel mixture inside the cylinder. If the engine’s valve timing lets that mixture escape or not compress properly, you usually lose power.
Valve duration is how long the intake valve stays open as the engine turns. Longer duration can help at high RPM, but it can make the engine less efficient at low RPM.
Term
dynamic tuning
Dynamic tuning is how the engine’s intake/exhaust airflow creates pressure waves that help fill the cylinders. If valve timing messes with that, the engine may not breathe well at the RPM you’re targeting.
Your engine has valves that open and close. Cam timing is the exact “schedule” for when those valves open and close, and it strongly affects how the engine runs at different speeds.
Intake charge is what the engine pulls into the cylinders to burn—mostly air, and sometimes fuel mixed in. If it gets pushed back or doesn’t enter correctly, the engine can run worse and pollute more.
Term
oil mist
Oil mist refers to tiny droplets of oil that get carried into airflow or combustion-related passages. In performance tuning discussions, it often comes up when combustion blow-by or crankcase vapors are being pulled into places they shouldn’t be, which can worsen emissions and contamination.
A camshaft has bumps that push the valves open. Those bumps are called lobes, and bigger ones usually mean the engine is tuned to run best at higher RPMs—so idle can sound rough.
“Fuel only” means the engine is relying on just gasoline/diesel (no extra boost systems like nitrous). That can make it harder to fine-tune how hard it launches compared to cars that can add nitrous.
Exhaust valve opening is the crank-angle timing when the exhaust valve cracks open to start letting spent gases leave the cylinder. Opening earlier can improve exhaust evacuation at higher RPM, but it also changes the balance of cylinder pressure and can reduce how much work the piston extracts from the power stroke.
Bleed down refers to the pressure drop in the cylinder once the exhaust valve opens and gases start escaping. That pressure loss reduces the force available to push the piston, so the timing of bleed down is a key trade-off for horsepower.
Turbocharged means the engine uses a turbocharger to compress intake air using exhaust energy. Because the exhaust drives the turbine, exhaust valve timing can affect turbo spool and how strongly the turbine wheel is fed by exhaust pulses.
Exhaust synergy is the beneficial interaction between exhaust pressure waves/pulses that helps move gases through the exhaust system more effectively. In a turbo setup, stronger pulses can increase turbine drive and improve boost response.
Turbo spool faster means the turbocharger reaches useful boost speed sooner after you apply throttle. Cam and valve timing changes can improve exhaust pulse energy to the turbine, reducing turbo lag and helping acceleration times like the 60-foot.
The turbine wheel is the rotating part inside a turbocharger that the exhaust drives. Exhaust energy spins the turbine wheel, which is mechanically connected to the compressor that pressurizes the intake.
Air velocity is how quickly air is moving through the intake passage. If it’s higher, the engine can pull in and keep more air instead of having it blow back out when the valve timing isn’t ideal.
It’s a way to measure how well the engine’s air passage actually lets air through. If the number is higher, the port is more efficient, so the engine can breathe better without needing bigger valves.
CFM (cubic feet per minute) is a flow-rate measurement used to describe how much air a cylinder head port can move. In this discussion, the key point is that “more flow on paper” doesn’t automatically mean more power—because the engine’s required airflow changes with RPM and displacement.
Top dead center is the point in the engine cycle where the piston is at its highest position. When people say “degrees after TDC,” they mean how far past that point the valve events happen.
Valve lift is how much the engine’s valve opens. Opening more can let more air in (or out), but it only helps if the rest of the engine setup can take advantage of it.
Atmospheric pressure is the normal air pressure around you. The speaker is saying that turbo boost gives you a bigger “push” to move air into the engine than just relying on normal outside pressure.
Boosting the turbo means the turbo is pushing more air into the engine than normal. More air can help the engine make more power, especially when airflow is the limiting factor.
A remanufactured head is a cylinder head that’s been rebuilt and repaired. If it gets resurfaced (machined flat), it can change how other parts sit relative to the combustion chamber, which can affect how well the engine runs.
Surfacing means machining the head so it’s perfectly flat again. Removing a small amount (like 10 or 20 thousandths of an inch) can change the shape/spacing inside the combustion chamber, which can affect fuel and power.
The injector nozzle is the part that sprays fuel into the cylinder. If it ends up sticking in farther after head work, it can change how the fuel mixes and burns, which can affect power.
The piston bowl is a small shaped pocket on top of the piston. It helps control how the fuel and air burn, and where the injector sprays relative to that pocket can change how well the engine makes power.
LIVE
Hello, everybody. Welcome back to the power driven podcast today.
It's kind of a fun topic for us. It's kind of middle of race season.
A big race just happened. Obviously, Myra UCC, but there's another big race
that during that event. Arguably bigger. Arguably bigger.
Who knew that? Way more competitors.
So we're talking about fast 72. You've been excited about this.
It's a pretty exciting thing that just happened in our industry.
And we're going to talk about like fuel only horsepower, air limited horsepower,
tips and tricks. We're kind of learning things we want to develop to help some of these competitors.
Yeah, we're talking about going fast on a limited turbo fuel only set up. So let's go quick recap.
72 fast. You're limited to a 72 millimeter turbo and it has to be a factory ECM has to be diesel
powered and not any 72 millimeter turbo. That's like a clout. You could you buy the turbo from
yeah, from VS racing. It's a knockoff Garrett GT 42 or 45 turbo. I don't remember. I think it's
the same turbo. You're not allowed to modify it. So it's not who can make the best 72.
So it's not a turbocharger design development class. It's everybody's the same turbo. You're
not allowed to touch it, modify it, port it, anything. And you have to have a diesel powered
engine and chassis and stuff. That's pretty, pretty fun and air to air intercooled. So you
can't do a water to air intercooler and get some trick, you know, ice box setup or something
doing something weird. So no injectables, nitrous, no water, no water,
methanol, nothing right. You can't inject anything. And so basically it's who can make the most
efficient diesel fuel only powered engine to run that turbo and then who can extract the most
power within their RPM range they're doing it. One of the things I think is really fun that was
discovered in this development last, you know, six months since they've been building up to this
race is that I mean, it's well known, but it's it's just proven time and time again,
peak power doesn't necessarily win races. Like there's been lots of engine dyno charts we've
seen along the way and chassis dyno charts. And I don't I don't think the most powerful
vehicles will actually won the race. Yeah, they didn't.
Matthew Parkers who won, but he had a public dyno appearance at Firepunks dyno showed graphs
and Cody Lambert had made more power on Firepunks dyno. And looking at the race, it looked like
Matthew Parker's truck was mile per hour and better than anybody. He was pulling away at the
end of the track on even in the finals against Stephen Grunke out of Canada. Yeah, Stephen was
a really good street racer really good on the tree. And Matthew Parker and Stephen told me he's
like, I didn't think anybody could drive around me if I got out and he said he got out half a
truck length on Matthew Parker. Matthew Parker drove around him. That's awesome dude. That's
crazy. And it was a second gen. So of course it warmed my heart. The second gen putting a hurt
on the second gen dominating UCC all the way around. Oh yeah, com real powered. It basically
it was basically the weekend of seconds. We you put the proper engine in a second gen. They're
pretty fast. They can the nice thing is they're light. They have less frontal area. I mean,
they're smaller vehicle. Okay, I think you're really nitpicking. I think they
look better. Okay, there. I don't know. But anyway, since the race, I've had many winners,
losers, anybody in between just competitors that competed competing that have reached out
interested in cylinder heads, camshafts. And there's a lot of like information that people have been
you know, willing to share that they can't disclose names and give away everybody's secret.
But since I don't want to say I'm the wizard of Oz, but I get to see behind the curtain on
what these other builds are. And then obviously talk with other builders, you know, Chase Fleece
and I talk a little bit and Berton, Steve Burton, a little bit new forms auto. He had some pretty
fast trucks there. I've got a lot of data on this and it's very interesting. And we start with
cylinder heads. Do we start with camshafts? What do we start? So yeah, so I mean, engine size,
even that was a thing is a 59 is a 64 is a 67 like what's what's the size because you're limited
in turbo. So I don't know where to start. Let's start with cams, because cams are very interesting
to us. I'm not sure if it's known publicly. A few people had shared some stuff they think I could
share but I would say the smallest cams out there were stock cams. Oh my gosh. And the biggest I
heard of were in that 210 215 intake duration size. So a stock cam just for reference, you know,
depends if it's a 12 valve 24 valve, but let's just call a stock cam anywhere from about a 160 to
175 duration of that's how long the intake valves open. And these guys are 210 215 degrees. And then
and then the exhaust side seems like everybody ended up right around a, you know, either a
stock exhaust about 180 duration to 210 220. I didn't hear of anybody bigger than a 220 exhaust
duration. Yeah, that was that was something I mean, you follow this people that don't know if I
hadn't done used to see will would have done 72 fast. He was super excited about this pretty hard.
And so he's always coming with new information that he's talked to someone about new ideas,
whatever, but something I heard, which I didn't follow it closely, but some builders were like,
yeah, big old big cam trying to make as much power as possible. And other builders are like,
yeah, stock cam stock cam close to stock cam was the play. And so it's like you have these
multiple very reputable people saying the exact opposite. And so that's what I thought was very
interesting. It's like, and then I mean, I like say like, different people had different opinions
on 5967 stroker, not stroker, but yeah, the one that was really surprising to
me is like, you have all these reputable shops, completely different like logic going at this.
We haven't personally done any testing on this raw because we've been working on Myers UCC truck
and I say we, I mean, Meyer and I mean, yes, I even bought some turbos. We were going to throw
I had got a bunch of part. I mean, I was, I was loaded. I was ready to like,
take this full on. And when I lost my wingman because he decided to go win UCC,
I was like, Myers, my wingman, he's just, he's my crutch that pushes me over the finish line.
Turns out being the go cart that pushes me over the finish line on these projects.
Well, and I are getting old. Myers like, come on, let's go ahead and work with our iPhone.
I just work like getting your charger going sounds like fun. Get in this thing of the force
sounds like fun fun, but I guess the big thing on the camshaft front in general,
it seemed like the freedom racing engines that made the biggest horsepower on the engine dyno
and the chassis dyno. When I saw stuff, they had some of these, you could say bigger size cams
that they found an engine dyno testing, but they did not have the highest mile per hour at the track.
And mile per hour is directly related to your average horsepower. If you have more mile per
hour than your competitor, if you have equal wind resistance, you put more power down and equal
weight. Everybody's at the same weight, 6,000 pounds, 6,000 pounds. And so if you're putting
more mile per hour down, you are going, you're making more power. Now a lot of these guys are
like, well, what if I get a botch 60 foot and I bounce or whatever I let off? There is a little
difference on how fast you accelerate in the 60 foot. However, it's counterintuitive. It seems like
the faster your 60 foot is, you generally make less mile per hour at the same elapsed time.
And so a soft 60 foot truck that's also lower mile per hour 100% is lower horsepower. And that's
something that never really made sense to me because I'm like, okay, a better 60 foot means at the
60 foot, you're probably going faster. So now how does your mile an hour at the eighth go down?
And the best thing I can figure the only way I can figure it is that obviously, as you're making
power, your heat soaking your engine, and in first gear, unconverter unlocked, this the lowest gear
possible, your drivetrain is not as efficient as it is later. And so your heat soaking your engine
with horsepower that's not being put down to the ground as well. And then once you get the top gears,
that's where you can actually like, I mean, you're in direct, your converters locked.
That's where you can really have your engine horsepower can put be put down to the ground
efficiently. If you just heat soaked your engine for in the first 60 feet, you're not able to put
down as much in the last was 600 feet. And so that's what's always like, that's the only way I
could picture that makes that makes sense. Because I've seen what you're talking about. But
originally, when I heard that, I was like, now that's wrong. Someone just doesn't know what they're
doing. Now they're with the slips back it up over and over. And this is from years playing with
the junk or drag truck will bring that up. And when I had a softer 60 foot, I would always have
better mile per hour out the back end. And I'm like, Why is this? Some people believe it's a theory
of, Well, you have more time under power with a softer 60 foot. And so there's more time for physics
to physics and and get more more mile per hour there. But you know, either way, it doesn't matter.
But there are some people that try to say, Well, that's just because there's 60 foes in there.
Now, there is a thing if you have a truck that can launch at 800 horsepower and stick it versus
one that can launch at 400 horsepower, obviously, in that first 10 feet, if you started 800 and
ramp up to 1400 horsepower, you're going to have higher average impulse or power put down to the
track, you're going to go quicker. And so there is an advantage to leaving with more power. But I
think that that directly is, you know, translating to your mile per hour, you have higher average
power output. But but it was very interesting, the biggest cams that seemed to make the best
peak numbers, we're definitely not able to make the most mile per hour.
Let's theorize about this, like, obviously, right now, we're just like thinking in our
minds, we don't have data. Why would that be like, I've thought a lot about this, like,
you know, the bigger the cam that you get, in general, they'll probably have a little bit more
overlap. You're gonna have a little bit more bleed, like trying to have better drive pressure
to boost pressure ratio, so you're going to have, you know, flow through the cylinders,
you have a really clean charge, cleaner charge. So we're trying to let you know,
let that almost boost, evacuate the cylinder a little bit, so you're bleeding off boost,
and maybe in a turbo limited application, that's just giving away a couple pounds a
minute that you can't burn into power. And I've thought about that a lot. So it'd be
better to have like very, very little overlap in a turbo limited setup.
And that that theory is well proven in the supercharge classes. There's a lot of
camshaft design based around factory supercharger, who can go the fastest on a factory Hillcat
supercharger, or a factory, you know, vortex supercharger, or a CTS V or whatever supercharger.
And in the camshaft world, they found more overlap, hurt the power when they were on an
air limited factory supercharger, when they got a big supercharger, you know, three liter
Whipple or something crazy, then that more overlap helped evacuate the cylinder helped get rid of
pumping losses of the exhaust, helping with some of that scavenging. And when they had extra,
you could say overhead and airflow, then the overlap helped them. But when they're air limited,
they'd be very, very careful on keeping the intake and exhaust valve open at the same time
for any amount of duration. And so that's well proven in superchargers, I can only imagine
I don't have data. But on this air limited turbo setup, there is some truth to that,
how much you're blown out the exhaust is wasted potential.
So it's interesting to me because why would the bigger cams then make more peak power,
but not average power? I mean, we're guessing obviously, because you say on the dyno from
what we saw, the bigger cams was making the big horsepower numbers, but they were not making
them all an hour at the track, they're getting walked by smaller cam guys. I'm just trying to
in my mind, think how do you make more than dyno and have that not translate to the track?
But I guess the data we don't have is they made a higher peak number. But
in the RPM window, they're there, whoever made the most average power is probably the guy that's
going the fastest there. And so bleeding it off down low. And so in the world of racing,
everybody advertises their peak number. It's the same with the cylinder head. People say,
Oh, my head flows 300 CFM because that's what the website on this stage four head said it flows.
But really assuming it does flow that that's the peak number. What does it flow? The valve is
different valve lifts throughout the whole thing. And so I could take a head that flows 300
and destroy it with Myers head that flows 280 because at 100 200 300 400 valve lift,
his head has put way more area under the curve, even though the peak isn't not there isn't quite
as high. Yeah. And so so it could be just simply people racing peaks and talking about
it but who actually made the most average power. I will say the truck that one had very, very high
torque numbers on the dyno graphs on Matthew Parker's truck. I think they there's a couple
flashes of his dyno graph there on the firepunk video and it showed a really big torque number.
And some of the other competitors are like, they're kind of cloning in like, is that why
he was so fast? He had this big torque number, which carried him out of the hole better. But I
know an engine and airflow design, a high torque number is directly related to a highly efficient
engine has really good volumetric efficiency. So I would argue, you know, if you don't have a big
torque number, you're not there. The fun thing about this class is you care about torque again,
like in Myers trucks and our race trucks, like, we're trying to limit torque, we're trying to
keep it out like we're trying to keep everything alive. Yeah. But in a 72, you're not going to
make enough torque. Yeah. Really to herself. It's like, dude, get after it. Yeah. Short shift it.
Do what you need to do. Yeah. It's super fun. Diesel stuff. Honestly, starting this podcast,
I was just going to talk about whatever. Now I want to put a 72 in the shorty
and do 72 fast in Texas. Like that sounds great. Did we mention there's a class? There's another
race in Texas. We didn't talk about that, but they decided to redo this again for more money
in Texas in September at NHRDA World Finals. So it's going to go down 140,000 dollars.
I think the winning purse is a hundred. This is like big money, big money. I'm going to start
getting people from gasoline stuff going, huh, what's going on? These diesel guys are like,
I got to learn this crap, man. This is better money than I'm getting in my big block crap.
So that's so yeah. So if you, you know, if you're thinking about 72 still time, I think
this class is going to go on. It's pretty fun that it's an NHRDA and ODSS. And so this is
September, right? This is in September, this next race for 140 grand. And I think it's still
affordable because I mean, I looked at the guy that won and he didn't have race wheels.
You know, he had a second gen long bed, you know, he'd lowered his truck a little bit and he was
a good racer and a good tuner. Don't take anything away from that. But at the same time,
he had a nice cylinder head, but he had essentially a, a stock 67 block
did not have a deck plate or force or anything special in there. It factory pistons. He told
me, I mean, we're talking like very affordable to do that, but he had tons of seat time,
tons of research made his truck go. I think factory pistons in a common rail is a great
option for this power level. Cause I mean, they don't, you don't have the nearest much
piston wall clearance to do the forge. So you can kind of absorb some of that stuff. I mean,
you're blown by numbers with factory pistons have been ridiculous.
Been awesome. So I mean, you're, you're capturing the pressure on top of the
piston. It's not going around. And so I think a factory piston in a 72 is probably,
I don't know how you beat that. Unless you make some custom high compression thing.
We'll talk about that later. Maybe. After we, after we compete, we'll talk about that.
I mean, until, until I make some is better than them. I sell theories and math and,
and hoping hopes and dreams, but, but, but yeah, the,
I do know some big name shops that took their typical 3000 horsepower recipe.
You don't want to point anybody out, but they took their 3000 horse recipe, big
valve relief pistons, big cam, deck plate, you know, fancy stuff. And they were struggling to
make a thousand horsepower. They were down 300 horsepower and they just, but if you're used
to building something that survives and lasts and you rely on nitrous heavy, you get this fuel
only stuff. And it's a totally different world. You can't have 600% injectors. They don't atomize
the fuel as well. You're not going to get as good of a fuel burn at this.
At this power. Remember that guy we used to work with who worked on top fuel cylinder heads?
Uh-huh. Yeah. She was like, he was like offended at how crappy the ports were.
And I guess they said, we don't care how much it flows. We just wanted to survive.
You know, like, yeah, the ports suck on top fuel because they don't need to flow good. We
just want to survive. This was a few years ago. So top fuel might have come a long way since then.
And this is one man's opinion. I've never seen a top fuel head, but he was a really good porter,
you know, Shane. So, and he'd won a lot of wallies and naturally aspirated, you know,
air limited, small block Mopar stuff. So I mean, he was pretty, pretty good air flow guy. And he
was just like, I'm offended at how terrible, but I think that kind of just goes back to your 3000
horsepower recipe. It's like at the high level, the game isn't necessarily how to make more power.
It's how to keep the thing alive. You know what I mean? And so, um, you're going to sacrifice a
lot of things for power that you would use in lower applications that were survived, but we'll
like, like thin valves, you know, the, the cut valves. And there's another part to that too is
like on that, that engine, like if I was trying to do something too fast, that'd be a terrible
engine for that because you know, valve reliefs and everything. He's pointing to his, yeah.
I'm pointing to my six Ford deck plate. That's in my UCC truck. You're talking to your 3600
horsepower engine. Exactly. Terrible 72 fast engine because like valve release, we're doing
valve relief so we can spin the RPM that we need to spin. So that way on the dyno, on the drag
ship, when we're trying to keep torque out of it or, you know, shifting at 6000 RPM,
it's not going to crash valves. We're talking about like pissing a wall for the heat. We're
talking about a heavy deck plate. I mean, the heavy deck plate, which that's a thousand pounds.
Yeah. 6000 pound, but like I'm trying to think what else, like we're just, I think,
but the valve reliefs mess with the swirl. It also messes with the compression ratio. There's
just a bunch of different things that we're doing to keep that engine alive in the situation we're
putting it in that would not be ideal. I would bet that the engine in my shorty is a far better
72 fast engine. It's just a basic it's a tow truck motor. Yeah. It's a 67 cast
piss in waggler street fighters and these two power driven head. Yep. Power driven head.
Just works. I was, I mean, while you're talking about that, there's a lot of technology that was
developed on injectors on this front. I was talking with Don M. He makes flux injectors there
and they had trucks picking up over a hundred horsepower going from one style of nozzle that
flux made to another on the dyno back to back the same turbo and he, he didn't make it sound like,
oh, I'm so smart. I knew this. It was just like, well, let's try this because this isn't making
as much power as we think it should compared to the competition. And so a lot of it was like kind
of trial and error stuff they found out, but there was, there was some stuff. I mean, I know
we've talked about with lending and DDP, they really like a six hole nozzle on these common
rails on these air limited sled pull setups and not every truck in the, let's say I have some data,
I can't share exactly, but the top, let's say I have some information from some of the top four,
five trucks in that contest, not all of them were on six holes, not all of them were on seven hole
injectors. Yeah. And everybody's just like, what? Like, how was that? How was that possible? How could
you and, and it wasn't that the people that won were like, aha, this is the best recipe I'm going
to do it. It's like, this is what I have. I'm on a budget and it just freaking worked. And, but
so many different recipes in there. I was very, I was very surprised. I will say that it did seem
like the RPM very quickly. These guys figured out they needed to short shift it. Anybody
shift in above 4000 RPM, they were, they were losing time. And so as an airflow guy that
really helps me to know, okay, if you're shifting at 4000, you don't need a 300 CFM head to feed a
67 at 4000 math, you know, math, usually maths, you need about 267 CFM to feed an engine
at 4000. But if that's not really making peak power, you, you might do better with a 250 CFM
head with a really efficient port versus a 300 CFM or laser port or whatever, slow velocity. Yeah.
I want to talk, we're kind of moving away from cams. I don't do that quite yet because I know
you have some theories on cams. This is now Will Terry's theory about intake valve opening event,
closing events. This is like the nerd stuff that a lot of people don't understand. Like we,
everybody understands 188, 220, a 202, you know, 220, these numbers, very, very few people
understand or even think to research intake valve and exhaust valve events, opening, closing
events. And those are actually very, very important, maybe even more so than the numbers
everybody talks about. So in camshaft design, there's the very most important, you know,
you read a book or whatever on camshaft design, the most important event in everything to do
with the cam is when the intake valve closes. What that is, that's the gateway that lets air
into the cylinder. So when it closes, no more air goes into the cylinder.
Your engine goes up and down. When a piston goes down, air floods in past the intake valve,
and it goes there. When the piston hits the bottom, you know, there's still air flown in,
there's a lot of air speed developed in the port. When the piston starts coming back up,
if you close the intake valve right at the bottom, when the pistons at the bottom,
you're missing the opportunity to fill the cylinder with air and air is what's, you know,
obviously, what you're burning the fuel with. And so that's how you're making,
you're making power. And so the intake valve closing event is like the most critical thing.
What's crazy is within engine platforms, let's say a 67 Cummins or two JZ or an LS,
there's a certain time just with the engine architecture and the way that the whole intake
system works, where it's the most ideal time to close the intake valve. And it seems to follow
engine families closely. So if you have a Hellcat engine or whatever,
it might like a little bit different intake valve closing event than a Cummins or a Super
Charge or Top Fuel Dragster. However, the intake valve closing event seems to follow the engine
really closely, but it's also tremendously dependent on RPM. If your engine is spinning at 10,000
RPM, there's no way you can get all the air in by the time the pistons at the bottom. And so you
need to leave the intake valve open a lot longer when the pistons on the way up. However, if you're
spinning an engine at idle, let's say you're a Cummins engineer, and you're trying to make your
12 valve have the very best cold starting characteristics on earth, the way it's going
to start the best in Siberia is if it closes the intake valve exactly when the pistons at
bottom dead center, because you don't want it to push any air out past that open intake valve.
And at a starting crank speed to 3,400 RPM, there's not very much piston speed there.
So for cold starting, I believe like a 12 valve, they close the intake valve very close to bottom
dead center when the pistons at the bottom. I want to take a pause and kind of like educate
the audience a little bit of Cummins if you're talking about RPM dependent on duration of
camshafts. You talked about the piston coming down the faster the piston goes down, the faster
the velocity of air comes without port and you talked about it develops velocity. And that means
it has momentum, the air charge in your cylinder that actually has momentum going into your cylinder.
So when your piston goes down, there's so much momentum that as the piston comes back up,
it still comes in from the momentum of the charge of the air because air has weight in density,
especially if the supercharger is very dense, there's a lot of momentum continuing to push it
in there. And if you're a very slow RPM, you don't have the momentum. And so the piston will push it
right back out and you have a lost charge. That's why he's talking about the bottom dead center
thing. But like, you know, for the long cars, their durations are ridiculously high because
they are so much RPM, they're putting it in when the pistons probably two thirds of the way back
up the stroke before they close the valve because there's so much velocity to that of the air coming
with momentum. So that's why we'll say like, you know, duration is very important with RPM. So
knowing your RPM range is going to really dictate the camshaft you're going to use. So
tell us describe that a little bit. And so then back on that same topic though,
a 12 valve cam, when I look at it, they're closing the basically closing the intake valve
for all intents and purposes at bottom dead center when the piston before it even starts
coming back up. And the only reason I could see they would ever do that is for cold starting. I
don't see any like, there's no engine design I've ever seen that closes the intake valve that early,
except basically things that they're trying to make start. They knew they had a turbo so they
could overpower their problems with turbo and they wanted to be able to start in the cold. And so
that's was simple solution, simple solution. Because yeah, I mean, really, I mean, we talk
about how awesome compression ratio is, really, we're kind of affecting the compression ratio,
because if you do the math compression ratio, you look at the swept volume versus, you know, the
the compressed volume. If your valve is open, at the very bottom, and you're pushing that air back
out, you just decreased your swept volume. And so yeah, mathematically, your engine's 17 and a half
to one or whatever. But if your valve is open for the bottom third, you just dropped your compression
ratio, we know that doesn't help. Yeah, yeah, especially for starting,
but also for just driving turbos making power like, yeah. So you think the intake valve opening is
happening way too early on a lot of the closing, sorry, yes, the closing, that's the big one on
a stock cam is is to on a 12 out 24 valve, it's a little bit later, it's more like 20 degrees
after bottom dead center. Well, you get some of these race cams, like let's say around a 208,
210 duration, something like that. Those are closing the intake valve like 50 degrees
after bottom dead center. So the pistons come up 50 degrees of crank rotation. So
what I'm seeing there is that probably makes the best power on the dyno at 3600 horsepower
or whatever, it's an RPM at that RPM at 3600 RPM, that is there. But at 2000 RPM, or 2500 in this
drag race, it's leaving the intake valve open too long, and it's blowing some of that charge right
back into the intake, which disturbs that that airflow that whole system of of pulses and dynamic
tuning. And so I think like a 210 cam, the reason that they're making better power is it is more
efficient at 3600 or 3800, wherever they may peak, but it is not as efficient as let's say a 188 to
20 or cold stage three, like a 181 is at 3000 RPM, because it's leaving the intake valve open too
long. And so these guys are trying to find the exact perfect cam. And there is no perfect cam.
There's a perfect cam for every RPM range. There is not a perfect cam that does all the
RPM ranges. So everything's a little bit of a compromise. In fact, in the gas world, that's
why they've gone to variable valve timing on all these new cars. Because if they make the cam events,
let's say they close an intake valve really early, well, you'll have a strong idle on your
wife's kid hauler, and they can trap more air, they can be more efficient, but then they also
want power at 8000 RPM, well, or 6000 where the red line is, they can change that cam and they can
adjust it so that it now closes the intake valve at 40 degrees after bottom dead center and traps
the right air for that RPM and they can map that obviously in a factory with their millions of dollars
of R&D and make the most efficient cam timing there. The reason the OEMs do that a lot is when
it reverts and pushes intake charge back, it causes emissions problems. Because you get fuel
coming back, you get oil mist and stuff out of the engine, you get so so they had to become
experts on cams just for their emissions side, but from performance side, you know, we can do that,
but you've ever seen a big lopie cam on a gas car? Well, that's because that cams way too big
at idle, that's why it lobes and sounds like crap. But that's also why it makes good power at 6000
RPM. It has the right cam timing events to that. So what I've been seeing once again on all these
cams is I'm looking at them, I think the intake valve closing is a little too late on these big
cams. And the on the small cams, they're not quite ideal up there at 4000 RPM where they're
shifting, but they're perfect. You know, in that mid range where they're running there.
Do you know what kind of RPM they're running down track when they're shifting on these trucks?
Like I don't even know that. Most of the guys are telling me they're shifting at 4000 because
there's not a power. And so Meyer could run some numbers on what that's pulling them back to.
They were getting into overdrive because they didn't have the RPM to go up there.
They tried to run out third, they went slower. So you shift at 4000 overdrive.
Mathematically, you shift at 400, it puts you down to 2750. But in real life with, you know,
the time it takes to shift and everything, they're probably going down to like
2850, 2900, something like that. So the three to 4000 is the range you're playing.
So yeah, these cams are designed for 4500, 5000 plus is definitely the wrong.
There's also, I mean, when you're talking about fuel only, like this is something I've learned a
lot about, like I had problems at UCC drag racing and a lot of it is because of this is
you're trying to, you're trying to get out of the whole fuel only all the fast guys are using
nitrous so that they can really tune how it comes out of the hole and they can throw the
different kits in at different percentages at different times to kind of tune the power out of
the hole. Your fuel only, you really only have what your tuning can let you do. And so I mean,
a lot of the strategy, especially on a 6000 pound vehicle is to try to get out of the hole as fast
as possible, get to that peak power as fast as possible. I bet like a cam that maybe doesn't
make best average power at 3500 or 43,000 or whatever, but can get you out of the hole will
may hurt you in mile an hour, but it will run, it'll get you out of the hole and run your best
60 foot, which helps you ET. And so I bet there's some stuff there too, not going super crazy on
the cam just so it's super efficient on that first half a second. So let's talk about cylinder head
stuff now. I mean, I mean, do you have concerns about exhaust valve opening as near as much as
there is because as your PM goes up, you need to start opening the exhaust valve earlier.
But the moment you open the second most important event is your exhaust valve opening event,
this moment you open the exhaust valve, that's when you start to bleed down that pressure,
that power stroke that's pushing the piston. And so there's a trade off there of any exhaust that's
left after the pistons at bottom didn't center and starts coming back up. It's stealing horsepower
from the crank to push the exhaust out any exhaust you blow out in the blowdown face when the piston
is going down is free. Other than it doesn't cost you pumping losses, but you're losing the pressure
on the some of your some pressure on the piston. But most of the work is done in the first 70 degrees
anyway on the piston. And so it's kind of a fine line. And it's very RPM dependent, because at higher
RPM, it takes longer to evacuate the exhaust, you need to open it earlier. And higher degrees of
rotation, not longer, but more degrees of crank rotation, more degrees of crank rotation. But
at higher PM, the fuel doesn't burn as fast at higher PM. So the power stroke technically
lasts longer at higher PM, because it's had less time to burn and expand. And so
it's like there's two competing things there. The final aspect because we're turbocharged,
if you crack that exhaust valve open early, you have more exhaust synergy, you get a harder pulse
that goes through that exhaust, it's the turbine wheel. Sometimes that makes more power hitting
that. So a lot of these cams, you know, for the years Colt and Hamilton have said that their
cams make turbo spool faster. The way they're doing that, if you look at the valve events,
they're opening the exhaust valve a little earlier, letting that exhaust pull squat and hit the
turbine wheel makes the turbo spool faster. So if you're trying to come out of the hole there,
their strategy of when is the right time to open the exhaust valve. And once again, that's something
like you can design and speculate, but really, you've got a test to figure out what what is the
best exhaust valve opening time. And like I said, that right answer is going to depend on the head
and stuff too. I mean, if you have an exhaust that moves a lot, you don't need to open the exhaust
valve as early, because it's going to evacuate faster, you have a higher flowing exhaust. But
if you have an exhaust cam load that smacks exhaust valve open really, really quickly, and you have a
really high flowing exhaust, you're going to drop that pressure pushing the piston way too fast,
and you're going to lose a little bit of your power stroke, more of it. And so once again,
that's all just like said, but that's the fun of the class is like, as an engine designer,
you get to play with all these different events, and figure out what makes the most power. If
you're choking on the turbine wheel, you could almost argue that you want a really long drawn out
exhaust event. So it doesn't hyper choke it when this big pulse comes, it's more of a of a long
duration on the exhaust. If you're not choking on the turbine wheel, and you have really good
exhaust bass pressures low, you like, man, let's run that power stroke longer and smash that exhaust
valve open way late in the system. And because you're not making 4000 foot pounds of torque,
you can get really aggressive on the cam timing before you start, you know, bending and deflecting
and breaking stuff where like on your UCC truck, we have to be careful when you're doing the big
nitrous on how aggressively we open the exhaust valve, because it won't open it bends the push rod,
it pulls the studs out of the head, I mean, yeah, on the rocker arm. So that is that is some
little separate subject a little sidebar here, but that was something really thrilled about with the
head on your truck because we've we've had lots of competitors, even Josh had issues ripping out
the studs holding down the rockers, been in stuff and you didn't have any issues. No, like we kind
of kind of spec the whole setup for that to to live. And you know, you drove off. We'll we'll
built a unit for sure. Yeah, so we're having some fun doing some fun stuff. All right, so let's move
on to cylinder heads because cams and cylinder heads, there's gonna be a lot of technology there.
Obviously, big things are happening in some of what's your thoughts on something about like
valve relief, low lift flow, you know, is that you want lots you want to kind of trap it so it
doesn't go across like what your thoughts on that. So to me, what the big key is because you can't
have the perfect cam, you have to operate in a fairly wide RPM range, at least 1000 RPM. So
there's no cam that's perfect at all that the way you band aid a cam or make cam timing less
important is having really high airspeed very efficient port, because if you have high speed
air moving in, if the cam isn't quite enough duration, it doesn't quite have enough to fill,
you're going to feel better if you have better airspeed coming out of the port. If the cam is
opening the intake valve a little too long at 3000 RPM, it's not going to blow as much back
out past the intake valve if you have better airspeed. So the most efficient or the port with
the highest coefficient discharge is going to be an advantage there. So yeah, you can make a
ginormous huge port big valve lazy that flows 300 CFM on paper. And it's not going to work as well as
you know, and the CFM demands of the engine are very, very dependent on the RPM and the
displacement of it. Like it's very simple math at 4000 RPM, a 67 Cummins 409 cubic inches,
they need 267 CFM ahead that flows more than that is not an advantage.
Interesting. But where you get in the gray area is like, do you design it for the shift point or
you design it for where it actually makes peak power? Maybe it's 3500, maybe a 255 CFM head is
actually the most efficient, if you can make it a little bit more more airspeed,
you know, so you're definitely in this in this level of competition, your stock valve size guy,
you're feeling like there's not really need for bigger valves. I mean,
if we cut the intake off, we can get stock valves there, you still, you still have points
in the lift when it first opens, because like, it starts opening exhaust valve, you know, when
the pistons up there near the top, well, you get about 70 degrees after top dead center, that's when
the engine has maximum piston speed. So theoretically, that's when it wants maximum airspeed coming in
or maximum CFM. If you have stock valves, and let's say that happens to be 300 camp valve lift,
if you can only flow, you know, 175 with a stock valve and a big valve, you can flow 200. If the
engine wants 200, the bigger valve is going to make more power at because your piston is trying
to push exhaust out if it has to fight to push exhaust, I'm talking about intake stroke, but
yeah, oh, sorry, like it. Yeah, an exhaust side. I think the exhaust, it's pretty good at pushing
out. There's a lot of energy. Okay. The reason we focus more on the intake side is there is
10 times the energy on the exhaust system to push it out. If you're off limit on the exhaust valve,
it's going to make a little difference in pumping losses, but there's so much there on the intake
side. All you have is atmospheric pressure or boost the turbo and your boost to work with.
You don't have nearly the pressure difference to work on that. So I'm saying a big valve,
you need bigger than stock to get to those numbers, but you don't need a 38 millimeter,
1.5 inch valve to be there. It's too much. So if you're keeping a shelf on the same
one with the budget right on a shelf on head, you're doing just a little bit larger than stock
intake valve. Nothing crazy though. If I can get the target numbers I want with 100,000 bigger,
I would do it. If I want to make sure we get there, I'm going to a 1.42 inch valve instead
of 1.29. So the few guys I'm working with right now is a couple guys already hit me up for Texas
and so much from one ahead. So I got all the work to do quickly so that they have time to test.
And I got to put my money where the mouth is like they can't take off their whatever brand
XYZ head and put mine on and lose power. I look like an idiot. So we've got to make sure that,
you know, we deliver, but I'm pretty confident that we're going to find some power. And
there's more to the head than just the flow to, I mean, something I found a little secret I'll
share with you guys. These top guys generally have been on a remanufactured head or remanufactured
head gets surfaced 10, sometimes 20,000. If you surface the head 10 or 20,000, that makes the
injector nozzle protrude further down into the piston bowl area. There's power making the fuel
hit lower in the piston bowl. Well proven. You talked to any of these top real top engine guys
that have dinos and access, they'll tell you, yeah, we need more. Well, it's hard to get custom
common rail injectors with a longer nozzle. We still do that on 12 valves, we would cut the
injector nut. It was an option we used to have on our 12 valves because we found power in 12
valves years ago, getting the nozzle protrusion. The way you do that on a common rail easy is you
just freaking deck the head 50,000 or whatever. You're taking thickness out of the cylinder head,
it's not as strong for a mega horsepower UCC engine because you've made the fire deck thinner.
But on a 72 fast air limited, you're chasing horsepower. There's some strategy there of
over surfacing the head to get that. Now if the valves are really shallow,
you then would have to put valve reliefs in the piston and valve reliefs destroy
volumetric efficiency, and especially the burn efficiency of your bowl area. And so once again,
these top guys have figured out, if you do that, you've got to sink these valves back so you can
run the cam that you want without valve reliefs because there's losses there. So the top guys
are a factory style piston for the most part. I mean, the ones I know of, I mean, I don't know
everything that everybody's running, but they're running a factory style. Some guys are running a
wide bowl QSB piston because they found in other air limited testing that there's power there.
But, you know, they're running that no valve relief, nozzle sticking down, and then they're
got to sink the valves. Well, if you sink the valves, you lose the low lift flow number on your
valves. Because and so it's like, it's like this like catch 22, like, is it more important to
have this big cam? Or is it more important to have low lift flow to feed the engine? That's kind of
where the math and the science comes in. But man, I would freaking love this. But I mean, I got guys
who like, you got any ideas and they run like 2050 engine oil and I was like, if you tried
thinner engine oil, you're like, no, and I'm like, we tested it, it picks up power,
but some power driven 540 in there. There's like 10 horsepower and 1000 horsepower truck
run 540. These guys are like, really? It's like over 2050. I was like, I run at my racetrack,
Todd and these guys run 2050 because they don't want bearing problems. And yeah, but again, if
you're at that limit, you're not making the crazy torque on the bearings you're making. And that's
what's cool is yeah, we're talking like 13, 1400 horsepower trucks, like you can make it survive
that pretty easily. Yeah, Cummins is well designed to handle that, which is crazy. Wow, like, it's no
problem. But theoretically, a more stiff cylinder wall is going to have better ring seal. And so
you're capturing more of the power you're actually making. And so technically a filled block or a
solid Hamilton block, I think number two, Steven grunky, he has a solid Hamilton block and a wet
head. So I know from other, you know, not personal tests, but things that the guys have shared with
me, those solid blocks pick up a little bit of horsepower, all things equal, you know, it might
only be 10 horsepower on 1000 or 1400 horsepower truck, but 10 horsepower times
they have 100 horsepower, you know, like the cam, the head of this, so it's like, it's pretty cool.
We've got water pumps and stuff. I mean, the lies guys, I mean, you could clip the water pump,
right? Some of these guys, you run electric water pump, you know, yeah, I'm electric. I saw
several belt driven water pumps in the finals. And I'm like, dude, there's like 10 horsepower there
No, I've thought about this a lot. Like you like I use the Haltex. So what would I do is I would
if I'm over, if I, if the race time, I guess I, yeah, I do race time. So that way when I'm,
when I left the button, alternator kills, like, don't burden yourself with alternator,
you can run electric lift pump if you want, you can turn it off if you want. Who cares?
Like, yeah, it's talking a couple seconds. Just turn it off for five seconds or six
seconds, whatever you need, and then kick it all back on. Like, why not? And then, I mean,
you don't have to worry about solenoids. You don't have to do fans. Like, yeah, just turn it
I think it would be really fun to build this type of truck and just like just the little
things and see what you could do. The problem, like I want to do it for Texas now, but I don't,
I don't have enough testing on the shorty and the rear suspension is not what it needs to be.
It would need to be four link to be competitive. I think they're leaving pretty good. They're
leaving hard. There's, there's some pretty smart stuff we saw. I thought it's pretty,
pretty good ingenuity. Really fun to see what guys think of and everybody's, I mean, I saw bed
covers on the top trucks, but at least two of the ones, I think maybe Stephen grunkies too,
at least two of the guys in the final four had bed covers on. You know, that's, that's wind
resistance. When you're going, we're going 117 miles an hour, they're climbing the fastest trucks
and the slower guys were like 112. We start running the math, 117 miles an hour. That's like 50
horsepower worth of wind load. Yeah. I mean, aerodynamics might pick up five horsepower
worth of, you know, or even more. Yeah. Maybe even, maybe more than 50, huh? There's probably like
well over a hundred horsepower. That's what I'm thinking about. Like the shorty is like the
lowest truck you're going to get in four wheel drive and still have a superior engine platform.
Like, and we know that's huge. There's a huge advantage in ride height. You know, I'm like,
I want to do it, but I don't want to ruin the truck with four link. I want to do it. It's the
ultimate street truck. It's the goal. Yeah. It's so much fun. You have my old school,
get some cal tracks, man. Oh, but anyway, back to the cylinder head drive. That helps a lot.
I'm just saying it may be worth not going crazy, crazy, but doing some good things and make that
because that truck will be so cool. And it's like, it's like 5,500 pounds. So just put a little bit
of weight of, you know, you have tack welded in so it's not bolt in, you know, but like just put
a little bit of weight in there. Yep. Pretty easy. Yeah, it'd be great. It'd be so much fun. I don't
want to ruin the rest of my year trying to get ready for another event. Well, that'd be a lot
of fun. I think the entries all sold out should be buying an entry in the black market or secondary
market with I don't know what they're like. There's only 64 entries on this one. They had
over 120 it in Indianapolis. So people selling tickets for like like 195 or something like that.
Like there's a lot. Now people that actually showed up like crazy. I don't know the entries
for this next class to you the next time. The fact the purse is bigger and there's less entries,
they had to have doubled the entry price, I would think, but I don't know. I didn't,
I didn't even know that they had a second race announced until it was sold out. I was like,
really? But it's all right. That means anybody I'm working with to help, I can help you and not
be biased because I don't have a horse in the race. I just want to make sure if you have my
stuff, you have the very best chance of winning because that's a fun little feather to put in
your cap to say, you know, something we designed this camshaft or this head is is is out there,
you know, put in work. The fun thing about the something about this class to me is
it's forcing innovation in areas we haven't really tried to do for a long time. We've really
just like how do we make more power and we have figured that out. We make more and
power. And that's pretty fun. Now it's like, okay, how do we, we don't, that's, that's not for
everybody. Like now it's time, okay, we dial it down and anybody can like, I'm not gonna say anybody,
but anybody could compete in this class who has engineering mindset, ingenuity, they can compete
in this class. Like you don't have to be like, this is not a high buck class. The trucks we saw
there were not million dollar trucks by any stretch of the imagination, or even half million dollar
trucks. There were some really, really nice ones there. But that was not a guarantee of success.
I saw some, some you could say appeared to be poorly put together, but well sorted trucks,
kind of like the junk or drag truck, you know, it's a piece of crap. But like, at the end of the
day, when I'd go to race events, because I had a lot of seat time in there, it just, it just worked
trucks that worked consistently 60 footed, didn't overheat, they didn't have to make a bunch of
tuning changes. Guys with seat time is were the ones that really, but none of the ones that wanted,
I see like, Oh my gosh, they're way out of the realm. They've got these super skinny, low rolling
resistance tires, and they're turning the four wheel drive off mid track, which once again,
could be a strategy. I don't like I said, I mean, I can do it. But you don't, you kind of want
four wheel drive for the shift. So that if there's any spin, there's no spin, it all goes there.
But, but I mean, there's all kinds of fun stuff to think about. I mean, at 6,000 pounds, I don't
think you have to worry about kicking the tires on the 34 So you just like once you get
to third, because yeah, because I it's an electric shift for an axle. So you could say kick the tires,
but on my once again, junker, when I was two wheel drive, I used to run the asphalt oval tires.
When I put true slicks on 34 felt way more violent with everything the same.
I was spinning and I had no idea it was spinning. And it wasn't like a hard spin, it was just
a control losing that impulse on the shift. But I will say this, once playing with that truck,
when I raise line pressure, I would go quicker with the same horsepower. It would, it would go
your less time between more, more pressure in a 48 valve body, it makes the shift firmer time
firmer and faster. And so there's less time you could say halfway between gears. And when you
see it on the dinos, you get more of a spike. When you have really violent valve body, the these,
you make a seven horsepower truck and when it shifts, it'll spike 900 momentarily, as it converts
all that engine rotational momentum into tire power momentarily. And so if you can on the
dyno shift through gears and make it spike higher numbers, you're doing, you're, you're helping
the transmission, you're going to go faster with the same setup. Is this class limited to factory
transmissions or guys are in turbo 400s? Like is that a thing? No transmission limits at all.
But the winners first and second place, they're both 48s, right? Yeah, there's no, I don't even
know if there was a single turbo 400 in it, honestly. I don't know if you could do it because
you can't you can't trans break no trans brakes. So that kind of takes out that one of the advantages
of the turbo 400 they have a better trans break is believed. So if that's gone, yeah, what, what
advantage do you have with the turbo 400 really? You might not if you don't have overdrive. Yeah,
maybe a bad transmission. The four gears, you know, we know this just from OEM stuff,
more gears go faster when you're limited on power. More gears, more problems, but 68.
Actually, I think about it. If the 68's efficient, I don't know how much loss it has
spinning everything in a 68, but six gears could be advantage. If it can lock, if it's unlocked,
you're losing all kinds of power. Yeah, I mean, you can lock. I don't know how that would work.
I don't know if the gear ratios you'd have to like start in second because I think you're
going to zoom out first so fast. Yeah, like you can't leave with the power you need to leave at.
So you'd be wanting to leave in like second or third or something. So then you're back to four
speed. What I would really like to try is is a 59 engine. Theoretically, the smaller
engine is more thermally efficient. But I don't know if you can get the turbo to come up as fast
in that 60 foot range when you need to gain power quickly. The thermal efficiency advantage
might be totally washed out and negated by getting it up to power faster with with more
cubic inches and maybe maybe a 20 over 67 is actually the play. I don't know.
That's where the dyno game is different than the drag race because like you can make an engine that
peaks high on the dyno, but there's so much more that goes into it on in a drag racing application.
But I do feel like with a chassis dyno, if you can get it to stick the tire, you could simulate
that and you don't have to just rely on the peak dyno numbers. You just Oh, yeah, you can.
What are we doing to go faster? Yeah. Well, needless to say, we're excited about fast into as are a
bunch of other people and it's pretty fun. There's a bunch of money in this class like real
big money like stuff that's not been in the diesel world really ever. I mean,
UCC has had some good money for sure, but not this level. No, yeah. I mean, I think it's cool
because it's such an entry level like I'm seriously sitting here thinking like I wonder if I can put
my daily in it. You know, like that's such a super entry level. He doesn't need anything crazy
to know to compete at that. And it's popular enough enough of other people are trying to compete in
it. It's like it's quite the challenge. Like cool would be cool to go there win and win a
bunch of money, but really it's cool to just like stack your crap against everyone else's and
because of the way the rules are set. It's not like it's like sure money always helps go faster.
You have unlimited budget. You can buy things that you weren't going to buy. However,
you don't need a bunch of money to be actually really competitive. You don't need like some
super fancy intercoolers. You got to have a factory air to air or you have to have an air
to air intercooler. He does. It's not like some super fancy turbo system. It's not like you can
spend a bunch of money on fiberglass and 49 inches and whatever else to make your truck
light. It's got to be 6,000 pounds. You don't need to spend a super easy to hit. You don't need an
expensive engine. Yeah, you're talking cast cast piston. I mean a factory 67 rods in it
with rods in it. You could buy a used factory 67 engine and put put rods in it. Even the
factory head and you could still be, yeah, you know, in the game go there. I mean, you're not
going to go as fast as a ported head guys, but you could be with factory cam factory head. You
could go pretty far. And that's what you're a good driver. I'm a terrible driver and that's
my main hold up. Like I'd like have to hire you to pilot a thing or something.
You're a pretty good one. It didn't matter as far as like my heart to you was like 30 seconds.
I mean, I saw a few guys struggling with their factory breaks and pushing through and red lighting
and they couldn't launch as hard as they wanted. So there's some innovation there. If you just
simply figured out how to make your breaks better than your competitor. I'm sure a lot of
guys have like line locks. Oh, not line locks like lightweight breaks, but I got 2008 AMs
from a Duramax. Like them things be breaking, but those breaks come off instantly or they drag. I
mean, that could be the difference. Like some guy could spend months and get another 50 horsepower
on the engine dyno and you spend a week making your breaks come off faster and hold so you
break lines. So they should release play. Now I adapt them down to three sixteenths because
that's my dodge. We can undo that, but I'm like there. I mean, there's so many areas for innovation
without spending tons of money to where people and and it's so great when you're out there and
you're beating people with like your plane and they're like, they're so fresh like in the junker.
They're like, what is Meyer doing? And it's really, he's just his break motor.
His break stone drag is going real right. You know, just something stupid like that. You know,
you never know. Never know. But anyway, guys, we're excited for this in September in Texas. It's
going to be a big event and a big finals there for the NHL finals. It's the whole finals of that
season. Plus ODSS is going to be a big event. Yeah, it's going to be pretty cool. So anyway, guys,
our time's up. That's a wrap this episode. If you're interested in 72 fast, we are excited
for you as well. We're going to be doing cylinder development, campshaft development. Will's
going to be busy. We hope you enjoyed the Will Terry show today. Really carry the team. He did a
great job. He's been researching this a lot. So it's just kind of natural, but it's hard for
me not to share. I've known so many secrets. There's even more that I can't share. I'm sworn
to secrecy and just out of professional courtesy, you know, there's more on the table that I would
give you, but there's a lot here and you guys are smart as well. You can figure your stuff out. But
there you guys, I hope you enjoyed this episode. Please, you'll help us out. Like and subscribe
to the channel. Let us help us grow and reach more people. If you have any questions, call us
to shop. You always want to get to the right parts. And yeah, we'll see you next time on the
Persian podcast.
About this episode
Fast 72 diesel racing rules and results set the stage for a bigger point: more dyno horsepower doesn’t automatically translate to more track speed. The hosts connect cam choices, injector and valve timing, and even head surfacing to why “peak power” can mislead—especially with a spec 72mm turbo and air-limited constraints. They also argue that consistency and transmission behavior (like line pressure and 48s) can beat raw power, with big money and upcoming Texas events adding urgency.
Todd, Will, and Myer dig into Fast 72, the new turbo limited diesel racing class that is already turning heads and stacking serious prize money. A single 72 millimeter turbo and a fuel only setup are producing six figure purses, and this episode breaks down why.
They start with the actual rules of the class. No nitrous, no water injection, no methanol, just engine, turbo, and chassis. From there they get into why the trucks making the biggest peak horsepower numbers on the dyno are not always the ones winning at the track, and why second gen Cummins trucks keep running away with it the same way they have been dominating UCC.
That leads into camshaft talk. Overlap, intake valve closing events, and how RPM range should dictate cam selection, and why a cam that makes huge peak numbers can actually bleed off boost and lose power down the track. The conversation then shifts to cylinder heads, covering valve sizing, port flow, and why a factory piston might outperform a forged piston at this power level.
There is also a quick detour into transmission durability, since the top two finishers in this class are both running stock automatics, plus a reminder that this is not a high dollar class. Anybody with an engineering mindset can be competitive here.
They close out talking about the next Fast 72 event in Texas this September, with a purse north of one hundred forty thousand dollars on the line for the season finale.
If you are into diesel performance, Cummins builds, or smart engineering beating raw horsepower, hit subscribe on YouTube and follow the show on your favorite podcast platform.
Everything the guys talked about when it comes to cams, cylinder heads, and turbo limited builds is the kind of work Power Driven Diesel lives in every day.
Head over to PowerDriven.com to check out the full catalog and get your own build dialed in.
