Kory Willis Tells All! What's The Diesel Industry's Future?!
About this episode
Corey Willis of PPI Tuning talks diesel emissions enforcement, the legal fight that nearly shut him down, and why he believes the industry’s future hinges on better testing and smarter, more localized enforcement. He recounts years of pressure during the Biden era, including criminal/civil exposure and California EO gridlock over hardware requirements. Corey argues deletes/removals aren’t a safe bet right now, but he pushes for standards based on real-world data, private-lab testing, and smog-style inspection that ignores readiness monitors. He also critiques aftertreatment “net benefit” claims and warns about low-quality overseas tune libraries and AI-driven misinformation.
Kory Willis is back! He joins the show to discuss everything emissions and diesel. You've seen all the news surrounding DEF and charges for deletes. Kory called in to discuss his experience fightiong his battle to keep his company PPEI alive despite the massive blows it faced with charges. Kory also discusses what we can expect to see from here, emergency vehicles dealing with reduced power mode in times of crisis, and much more! Thanks for carving out some time for the show, Kory. Listeners, this one is a good one. Enjoy!
emissions conversation
"We have an OG making a lot of banter on social media, probably spearheading the emissions [25.6s] conversation I'd say in the diesel space. [27.8s] Definitely spearheading."
In diesel, “emissions” is about how much pollution the engine puts out. The conversation is about meeting rules for cleaner air without giving up too much performance.
The “emissions conversation” in diesel performance usually refers to how diesel engines meet environmental regulations while still delivering power. It often includes topics like emissions control systems, compliance strategies, and how aftermarket tuning interacts with those systems.
PPI Tuning
"I guess, without further ado, we have Corey Willis from PPI Tuning. [33.7s] Corey, how are you doing, man?"
PPI Tuning is a company that modifies diesel engines after they’re built. They typically adjust the computer settings so the truck or car feels stronger and drives better.
PPI Tuning is an aftermarket diesel tuning company. In diesel circles, “tuning” usually means calibrating the engine’s control modules (often via custom software) to improve performance and drivability while staying within safe operating limits.
Biden administration
"...the reality is, it's under the Biden administration. Man, if you were in the performance industry, you felt it..."
They’re talking about the federal government leadership at the time and how its rules affected diesel truck modifications. When administrations change, enforcement and regulations can change too.
The “Biden administration” is referenced as the policy environment under which the speaker says enforcement and regulation affected the diesel aftermarket. For listeners, this matters because emissions rules and enforcement priorities can directly impact what modifications are legal and how aggressively they’re targeted.
aftermarket performance industry
"If you were in any industry, but really, aftermarket performance industry, I mean, everybody been living on pins and needles..."
The aftermarket performance industry is the part of the car world that upgrades cars after you buy them. For diesels, that often means adding parts or software to make the truck faster or more fun to drive.
The aftermarket performance industry is the ecosystem of companies and shops that modify vehicles after they’re sold—often to improve power, handling, or appearance. In diesel circles, it commonly includes tuning, exhaust, and other hardware changes aimed at increasing performance.
removing emissions off of them
"...criminal convictions during that time for modifying trucks, removing emissions off of them, which generally, and historically, has always been a civil penalty."
This means taking out or disabling the parts that help a diesel truck meet pollution rules. People do it for more power or fewer limits, but it can be illegal and can get you in serious trouble.
“Removing emissions” refers to deleting or disabling emissions-control equipment on diesel trucks, typically to reduce restrictions and sometimes to avoid emissions-related limits. This is often tied to illegal or heavily regulated practices, which is why it can lead to enforcement actions.
civil penalty vs criminal convictions
"...criminal convictions during that time for modifying trucks, removing emissions off of them, which generally, and historically, has always been a civil penalty. I mean, it just, it got escalated..."
A civil penalty is usually a fine or administrative punishment. A criminal conviction is a much bigger deal—it's a legal case that can lead to a criminal record.
A civil penalty is typically a fine or enforcement action without criminal charges, while criminal convictions involve prosecution and potential jail or criminal records. The speaker is describing how enforcement shifted from mostly civil outcomes to more serious criminal consequences for certain modifications.
emissions testing saga
"The whole emissions testing saga, I've griped about it for six plus years now. That was part of my consent decree that we're getting figured out now since I had to sue on last April."
This is about the rules and procedures for checking whether vehicles or emissions-related products meet legal standards. When testing takes a long time or keeps changing, it can make it hard to sell or use the product.
The hosts are referring to a long-running struggle around how vehicles and emissions-related products are tested and regulated. In diesel performance circles, these processes can determine whether a product can be sold or used legally, and delays can stall development and sales.
Morgan Six Plus
"... emissions testing saga, I've griped about it for six plus years now. That was part of my consent decree tha..."
The Morgan Plus Six is a sports car made by Morgan, designed to be fun to drive. It has to meet emissions rules like any other road car, and the podcast mention suggests there were problems or delays with emissions testing or compliance paperwork. If you’re buying one, you’d want to confirm it’s properly registered and passes the required emissions checks for your area.
The Morgan Plus Six is a modern sports car from Morgan, built for driving feel and classic-style road presence, typically powered by a turbocharged engine. It’s significant in a podcast context because it can be discussed around emissions compliance and testing requirements, especially when there are long-running regulatory or paperwork issues. That “emissions testing saga” reference suggests the Plus Six is part of a specific consent-decree or compliance story.
consent decree
"That was part of my consent decree that we're getting figured out now since I had to sue on last April. So we're going to April 15th of 2025."
A consent decree is basically a court-approved agreement that says, “Here’s what you have to do, and here’s what the government will do if you do it.” It’s often used to resolve disputes without a full trial.
A consent decree is a legal agreement between a government agency and a party (often reached after a lawsuit) that sets specific obligations and timelines. In the automotive/emissions context, it can dictate what must be fixed, how compliance is proven, and when enforcement actions are avoided.
sue the government
"...getting figured out now since I had to sue on last April. So we're going to April 15th of 2025. I had to sue the government over this consent decree."
They’re saying they went to court against the government because the rules or enforcement weren’t being handled the way they expected. That kind of legal pressure can force regulators to follow through on decisions.
The speaker describes taking legal action against the government to resolve regulatory or compliance issues tied to emissions testing and the consent decree. This highlights how diesel-related products can be affected by enforcement timelines and shifting policy interpretations.
approved by California to be able to sell the product
"Just for the listeners here, that specific topic that you bring up is you being approved from like the state of California, right? Like you have to be approved by California to be able to sell the product..."
California often has stricter emissions rules than other places. If a product isn’t approved there, you may not be allowed to sell it in California.
California has its own emissions and vehicle-related product approval framework, which can be stricter than federal rules. If a product isn’t approved by California, companies may be unable to legally sell it in that state—even if it’s available elsewhere.
California had changed a lot of their policy midway
"And California had changed a lot of their policy midway. There's a lot of things that happened that I'm not making public just yet, but there's a lot of things that were inconsistent that happened."
They’re saying the rules changed while they were in the middle of getting approval. When that happens, it can slow everything down because you may have to redo work to match the new requirements.
The speaker suggests that California’s emissions-related policies changed during the approval/testing process, creating inconsistency and delays. For diesel performance products, policy shifts can affect what documentation is required, what compliance standard is applied, and whether approvals remain valid.
emissions compliance vs aftermarket tuning hardware
"[526.7s] And long story short, that inhibiting [530.0s] that inhibited us from being able to [532.0s] get an actual EO, but our consent [535.0s] decree required us to have an EO, ... [565.8s] So like, you know, if you sell an [567.1s] EFI live device to someone and they [569.4s] get a tune, but, you know, two [570.7s] months later, they would go to thirty threes"
Aftermarket tuning can be complicated by emissions rules. Even small changes to the vehicle setup can require extra approvals, so companies may have to offer different versions of their tuning hardware to keep everything legal.
This segment highlights the tension between emissions regulations and aftermarket tuning. Even if the tune is the same, regulators may require separate approvals for different configurations (like tire sizes), which can force tuners to sell multiple hardware/software variants to stay compliant.
EO (Executive Order)
"[530.0s] get an actual EO, but our consent [532.0s] decree required us to have an EO, [536.7s] which is, you know, the state of [538.8s] California issues that"
An EO is an official “permission slip” from California emissions regulators. If a tuning product has an EO, it’s allowed under CARB’s rules; if it doesn’t, selling or using it in California can be restricted. It’s basically a compliance stamp.
An EO (Executive Order) is CARB’s formal approval for certain emissions-related products, including some engine tuning components. The speaker is describing how their consent decree required them to obtain an EO, and how that approval determines where the tuning can be sold/used.
CARB (California Air Resources Board) EO policy
"[548.6s] Well, in the midst of it, like [551.0s] somewhere around twenty one, twenty [552.3s] twenty two, [554.5s] CARB themselves actually had changed [557.1s] some of this policy and made it to"
CARB is California’s agency that enforces emissions rules. They issue approvals (called EO’s) so certain engine tuning products can be sold and used legally in the state. The rules can change, and that can force companies to redesign or re-approve their products.
CARB (California Air Resources Board) is the agency that regulates emissions in California. In this segment, the speaker discusses how CARB’s policies and requirements—like needing an EO (Executive Order)—affect whether and how tuning products can be sold and used legally.
tire size revision
"[554.5s] CARB themselves actually had changed [557.1s] some of this policy and made it to [558.5s] where like if a customer just got a [560.7s] tire size revision, I was going to [562.7s] have to sell them like a whole new [564.6s] piece of hardware."
A tire size revision means changing the tire diameter/size from what the vehicle was originally configured for. In emissions-compliance terms, that can trigger re-approval requirements because it may affect how the vehicle’s calibration and emissions behavior are validated.
EFI Live
"[565.8s] So like, you know, if you sell an [567.1s] EFI live device to someone and they [569.4s] get a tune, but, you know, two"
EFI Live is a device/software used to tune a diesel (and other vehicles) by changing the engine’s settings. The point in this segment is that legal/compliance requirements can depend on the vehicle’s setup, not just the tune itself.
EFI Live is an aftermarket engine tuning platform used to modify vehicle calibration and controls. Here, the speaker references selling an EFI Live device and then needing additional hardware approvals when the customer changes tire size.
AutoCal
"[575.3s] The way that was written was it was [577.3s] going to be required that I had to [578.6s] sell them a whole nother AutoCal or [581.2s] EFI device or whatever device just [583.2s] to get a tire size update."
AutoCal is a tool that lets tuners update a vehicle’s computer settings. The point here is that the speaker is saying customers shouldn’t have to buy extra hardware just to get something like a tire-size update.
AutoCal is a brand name for an aftermarket tuning/programming device used to update a vehicle’s calibration. In diesel performance circles, it’s commonly paired with tuning files to change parameters like fueling and shift behavior.
EFI device
"[577.3s] going to be required that I had to [578.6s] sell them a whole nother AutoCal or [581.2s] EFI device or whatever device just [583.2s] to get a tire size update."
An EFI device is a gadget that helps a tuner talk to the car’s computer. The speaker is criticizing the idea that you’d need to buy extra hardware just to make a small update like tire size.
An EFI device is an aftermarket electronic interface used to communicate with and modify engine control settings. In tuning workflows, it can be required to apply specific calibration changes, such as tire-size updates or performance tunes.
tire size update
"[578.6s] sell them a whole nother AutoCal or [581.2s] EFI device or whatever device just [583.2s] to get a tire size update."
When you change tire sizes, the car needs to know the new diameter. Otherwise, it may read your speed wrong and the car’s systems that rely on wheel speed can get confused.
A tire size update recalibrates the vehicle’s speedometer/odometer and related calculations to match the actual tire diameter. Without it, the car can report incorrect speed and can affect traction-control or drivetrain logic that depends on wheel speed.
emissions approvals
"[601.1s] have some cardio stuff and what was [603.4s] approved in twenty twenty on some of [605.2s] our Duramax stuff is is vastly [607.3s] different than some of the Cummins [608.4s] stuff."
Emissions approvals refer to regulatory authorization for specific engine calibrations/tuning strategies under emissions rules. This matters because what’s allowed can vary by engine platform and model year, which affects whether a tuner can legally sell a given calibration in certain states.
Cummins
"[605.2s] our Duramax stuff is is vastly [607.3s] different than some of the Cummins [608.4s] stuff. So like, I can sell [610.9s] a Duramax tune to the state of [612.2s] California for an existing piece of [613.8s] hardware. Yes. [615.6s] But the Cummins stuff that got"
Cummins is a diesel engine brand used in trucks (often Ram). The point is that tuning that’s approved for one diesel platform may not be approved the same way for another.
Cummins refers to the Cummins diesel engine family used in many Ram (and some other) trucks. The speaker contrasts Cummins-related tuning approvals with Duramax, highlighting that emissions/calibration rules can be different across engine platforms.
Duramax tune
"[608.4s] stuff. So like, I can sell [610.9s] a Duramax tune to the state of [612.2s] California for an existing piece of [613.8s] hardware. Yes."
A tune is software changes to the truck’s computer to change how it runs. Here, they’re talking about being able to sell a tune in California without requiring new hardware.
A tune is an aftermarket calibration change to the engine/ECU that can alter fueling, boost, throttle response, and sometimes transmission behavior. In this segment, the speaker is discussing selling a Duramax tune that’s compliant/approved for a specific state using existing hardware.
selling hardware with tuning software (hardware-locked tune updates)
"I have to sell hardware with the tune and I can't sell tune by itself... I'm not able to email that tune file."
They’re talking about how some tuning companies require you to buy certain hardware to get tune updates. Instead of just sending you a file, you may have to use their system to load the update.
The speaker is describing a common aftermarket tuning business model where tune access is tied to specific hardware. This can limit how customers receive updates (for example, needing an in-person or device-based update rather than emailing files), which affects pricing and convenience.
tune file
"you have to update a tune file. But I'm I'm not able to email that tune file."
A “tune file” is the saved computer update that gets loaded into the truck. It contains the changes the tuner wants the engine to use.
A “tune file” is the actual data package containing the calibration changes that the tuning device loads into the engine control unit. The transcript highlights that some hardware/software setups require updating or transferring these files rather than sending a simple standalone product.
Duramax
"hey, any Duramax guy that's out there and you're going to do it on EFI live"
Duramax is GM’s diesel engine used in certain Chevrolet and GMC trucks. When someone says “Duramax guy,” they mean a person who owns one of those diesel trucks.
“Duramax” is the common name for General Motors’ diesel engine family used in Chevrolet and GMC trucks. In this context, “Duramax guy” means owners of those GM diesel trucks who use tuning tools like EFI Live.
tire adjustment
"they want to tire adjustment like it's not like it's a fifty dollar fee."
Tire adjustment is when the truck’s computer is told what tire size you’re running. That helps the speedometer and driving systems stay accurate after you change tires.
“Tire adjustment” refers to updating the vehicle’s calibration so the speedometer/traction-related calculations match the actual tire size. Many tuning systems require this because changing tire diameter can otherwise cause incorrect speed readings and related control behavior.
tuning company
"And like as a, you know, we're primarily just a tuning company. You're had a business like so it's a no-go zone."
A tuning company adjusts the computer settings in your diesel to make it drive and perform differently. Depending on the rules where you live, tuning can also affect emissions equipment.
A tuning company specializes in calibrating a vehicle’s engine control unit (ECU) to change performance characteristics like power delivery, torque, and drivability. In diesel circles, tuning often intersects with emissions equipment and regulatory compliance, which is why government agencies may be involved.
SVA side
"...working directly now with with folks in the admin on the SVA side of this administration, the EPA side..."
The “SVA side” sounds like a particular government group involved in vehicle rules. The host is saying they’re working with multiple agencies, not just one.
“SVA side” appears to refer to a specific government office or program within the administration that’s relevant to vehicle policy or emissions enforcement. The speaker implies they’re coordinating with that group alongside EPA and other federal stakeholders.
White House
"...the EPA side, even some with the White House and then congressmen and senators involved."
The White House is the top level of the U.S. government. If they’re involved, it usually means the topic is important and being handled seriously.
The White House is the executive branch leadership in the U.S., and its involvement in policy discussions typically signals that the issue is high priority. Here, it’s mentioned alongside EPA, Congress, and senators, suggesting diesel emissions/tuning policy is being coordinated at a high level.
congressmen and senators
"...even some with the White House and then congressmen and senators involved. And we've got a pretty good little team..."
Members of Congress (representatives and senators) can influence federal regulations through hearings, oversight, and legislation. In the diesel industry context, their involvement often relates to how emissions rules and enforcement affect tuning, emissions systems, and aftermarket support.
diesel freedom coalition
"...we've got a pretty good little team, a diesel freedom coalition team. And and they everybody just gets it."
This sounds like a group of people who are trying to protect diesel owners’ rights—especially around tuning and modifications. They’re working with lawmakers and agencies to address rules that affect what you can do to your diesel.
A “diesel freedom coalition” refers to a coordinated group advocating for diesel owners and the aftermarket—often focused on maintaining or expanding access to tuning and emissions-related options. In the context of the episode, it’s presented as a team working with government stakeholders to resolve regulatory issues.
emission systems
"I was trying to basically sell them that there's a real problem out there, like with these emission systems. And it's like you're trying to sell the problem."
Emission systems are the parts on a diesel that clean up the exhaust before it leaves the tailpipe. If something in that system fails, the truck can run poorly or even trigger warning lights.
“Emission systems” are the factory hardware and controls that reduce pollutants from a diesel engine, such as exhaust aftertreatment and sensors. They’re designed to meet regulations, but they can be complex and expensive to diagnose or repair when they malfunction.
bureaucracy and government set up has gotten "screwed up" over the years
"The way this bureaucracy and government set up has really gotten screwed up over the years. So although there's a problem..."
They’re talking about how the rules and the way they’re handled can get messy over time. That affects what companies have to do to keep diesel vehicles legal and compliant.
This is a discussion about how regulatory frameworks and administrative processes evolve over time and can become inconsistent or burdensome. For diesel owners and builders, that can translate into shifting compliance targets, paperwork, and enforcement timelines rather than straightforward technical fixes.
emissions regulations can't be fixed by "turn a switch"
"So although there's a problem and we could directly see the problem to just turn a switch and, you know, make emissions fall off is like that's just not how it works."
You can’t usually fix emissions with one simple change. The engine and exhaust-cleaning parts have to be redesigned and retested so they work correctly in all the real-world conditions.
The host is pushing back on the idea that emissions can be solved instantly. In reality, emissions compliance depends on calibration, hardware behavior, durability requirements, and how the whole system responds over time—so changes usually require engineering updates and regulatory processes.
emissions removal
"So whenever people call us and obviously we can't sell emissions removal stuff or anything like that, but generally what people were always asking for..."
“Emissions removal” means taking out or turning off parts that clean the exhaust. People do it to avoid emissions problems or improve performance, but it can be illegal and can make the truck pollute more.
“Emissions removal” refers to deleting or disabling emissions-control hardware (like aftertreatment systems) to reduce exhaust restrictions or avoid emissions-related issues. It’s often discussed in the diesel world because it can change drivability and compliance, but it can also create legal and environmental problems.
exhaust aftertreatment
"One, a lot of these parts are come from China that are in the exhaust and we could be destabilized..."
Diesel exhaust aftertreatment is the system that cleans up the exhaust before it exits the truck. If replacement parts in that area aren’t reliable or properly made, the truck may not clean the exhaust the way it should.
“Exhaust” parts coming from overseas is tied to the aftertreatment system, which includes components designed to reduce soot and NOx before gases leave the tailpipe. When aftermarket parts are used in these locations, fitment, durability, and emissions performance can be affected.
aftermarket parts supply chain risk
"One, a lot of these parts are come from China that are in the exhaust and we could be destabilized..."
They’re basically saying some aftermarket parts may not be consistent in quality. If the parts aren’t dependable, you can end up with problems sooner than you’d expect.
The speaker is raising a supply-chain concern: aftermarket components sourced from China may introduce variability in quality, materials, and long-term durability. In diesel performance and emissions-related contexts, that can translate into reliability issues and inconsistent performance.
emissions enforcement
"I'm going to get rid of emissions right out the gate... regardless of what the government enforcement is, that's going to happen."
Emissions enforcement is the government making sure vehicles don’t pollute more than allowed. For diesel engines, it usually means rules about exhaust cleanup systems and proof that the vehicle meets those limits.
Emissions enforcement is how regulators require vehicles and engines to meet pollution limits, usually through testing and compliance rules. In diesel discussions, it often centers on how manufacturers and fleets respond with hardware changes, software calibration, and documentation.
Biden era national compliance initiative
"The heaviest hand that the government's ever had was during the Biden era under that national compliance initiative... I think it was 2019 to 23."
This sounds like a government crackdown period where regulators focused harder on whether diesel vehicles were meeting emissions rules. The host is saying it changed how the industry operated and how big the compliance problems became.
The “national compliance initiative” refers to a period of intensified federal oversight and enforcement aimed at diesel emissions compliance. In the transcript, it’s tied to a specific timeframe (2019–2023) and described as having major industry impact.
diesel companies
"They heard 60% of the American diesel companies."
When they say “diesel companies,” they mean the businesses involved with making or selling diesel vehicles/engines. The point is that enforcement didn’t just hit one small group—it affected a lot of companies.
“Diesel companies” here likely refers to manufacturers, importers, or engine/vehicle businesses selling diesel products into the U.S. market. The transcript claims a large share of them were affected by enforcement, which is important context for how broad the compliance ripple effects can be.
delete crisis in America
"...the delete crisis in America got three times bigger."
In diesel talk, “delete” usually means bypassing or removing the parts that clean exhaust. The host is saying that when enforcement gets stricter, the problem can grow instead of shrinking.
“Delete” in diesel culture usually means removing or disabling emissions-control components (often for performance or cost reasons). Calling it a “crisis” suggests enforcement and compliance pressure can drive more illegal or risky behavior, and it can also expand as products move across borders.
international sales to America
"But what happened is... it got three times bigger from international sales to America."
This refers to how diesel products sold internationally can end up in the U.S. market, affecting overall compliance and enforcement outcomes. The transcript suggests the “delete crisis” expanded partly because more activity shifted from domestic to international channels.
emissions thresholds
"No, it's because the manufacturers can't themselves can't sustain the the the current emissions thresholds. It's too high. Yeah, it's not achievable. And that's why"
Emissions thresholds are the legal limits for how much pollution a vehicle is allowed to put out. If the limits get stricter, car makers have to redesign parts of the powertrain and exhaust system so the car can clean up its exhaust enough to stay within the rules.
“Emissions thresholds” are the maximum allowable pollution levels (like NOx, hydrocarbons, and particulate matter) that vehicles must meet to be legal. When thresholds get tighter, manufacturers may need major changes to engines, fueling, and aftertreatment systems to comply.
emissions-system fault codes
"...someone's asking, What do I do about this code? Because my trucks derated? Yeah..."
A “code” is the truck’s way of saying something is wrong. If it’s related to emissions equipment, the truck may reduce power until it’s fixed.
The speaker references “code” in the context of trucks derating, which implies an emissions-related diagnostic trouble code (DTC). These codes can trigger protective power limits and require correct repairs to restore normal operation.
derated
"...someone's asking, What do I do about this code? Because my trucks derated? Yeah, I have I have a reductant tank heater..."
Derated just means the truck won’t make full power. The computer does it to protect the engine and emissions parts, usually when something isn’t right.
“Derated” means the engine’s power is intentionally limited by the vehicle’s control system. In diesel trucks this often happens when the emissions system needs protection or when a fault is detected, reducing torque to prevent damage.
reductant tank heater
"...Yeah, I have I have a reductant tank heater and, you know, GM six months out..."
That heater warms the fluid the truck uses to clean exhaust. When it’s cold, the fluid can get too thick, so the heater helps the system work properly.
A reductant tank heater warms the diesel exhaust fluid (often called DEF/AdBlue) stored in the reductant tank. Heating helps ensure the fluid stays usable in cold weather so the emissions system can dose it correctly.
service protocols
"...they wanted you to follow these protocols that would have like bankrupted your business. You know, we..."
“Protocols” are the required steps you’re supposed to follow when fixing or handling a problem. The speaker is saying those rules were so strict they could have made their business lose money.
“Protocols” here suggests required procedures—likely emissions-system service steps, warranty/repair workflows, or compliance-related rules. The speaker implies following them would have been financially harmful to their business.
new hardware required for adjustments within tested specs
"But the big [1044.8s] thing is is basically any [1046.9s] adjustment that you would [1048.1s] need to make, even if it's [1049.4s] within the spec of things [1050.8s] that you've tested. Yeah. [1053.3s] That required new hardware."
The speaker is describing a common engineering reality: even if an adjustment is “within spec” for performance or safety, it may still require new components (“new hardware”) to implement it correctly. In practice, that can mean updated sensors, calibration, wheels/tires, or other parts that must match the tested configuration.
stock system
"been done. We made the most power on the stock system and we passed emissions on everything."
“Stock system” means the truck was basically left as the manufacturer built it. They’re saying they were able to get strong results while still keeping it compliant with emissions testing.
“Stock system” refers to the factory configuration—factory emissions equipment and factory calibration. When they say they made the most power on the stock system and passed emissions, they’re emphasizing that their approach maintained emissions compliance without needing to fully replace hardware.
passed emissions
"we passed emissions on everything. The only thing we didn't pass emissions on was a truck that wouldn't pass on stock."
They’re saying the truck’s exhaust met the legal emissions limits during testing. For diesel builds, that’s a big deal because making more power can also change how much pollution comes out, so you want proof it still passes.
“Passing emissions” means the vehicle met the required exhaust/evap emissions limits during a formal test. In diesel performance circles, this is often the hardest hurdle because tuning for power can change fueling and exhaust behavior, so companies validate results both before and after modifications.
SEMA garage
"And that was a I think a 2021 3.0 E 46 Duramax. Yeah, that's the only one that actually wouldn't pass stock at the time at SEMA garage... But then SEMA garage"
They’re referring to a professional testing location (SEMA Garage) where vehicles can be tested under controlled conditions. The host is saying they verify results at their own shop, then confirm again at SEMA Garage.
SEMA Garage is a testing facility associated with the Specialty Equipment Market Association (SEMA), commonly used for vehicle evaluation and emissions-related testing. The speaker is describing a workflow where they test at their own facility first, then go to SEMA Garage for additional verification.
certs
"...it's like I've spent like $100,000 in certs. And I never got a freaking cert even though I passed all the tailpipe testing..."
“Certs” are approvals or paperwork that say a vehicle meets emissions rules. In this story, the speaker passed the exhaust test but still didn’t get the certification.
“Certs” here likely means emissions-related certification documents or approvals tied to passing emissions requirements. The speaker’s frustration indicates that passing tailpipe testing didn’t translate into receiving the expected certification.
tailpipe testing
"...I never got a freaking cert even though I passed all the tailpipe testing like that's ridiculous."
Tailpipe testing checks the exhaust coming out of the vehicle. It’s basically a “how dirty is it right now?” test to see if the emissions system is doing its job.
Tailpipe testing measures what a vehicle actually emits from the exhaust. It’s used to confirm whether emissions-control systems are working and whether the vehicle meets the applicable standards.
PTL
"...I think labs like, you know, PTL and others like that, like that's that's actually the future of emissions testing... like a lab like PTL or any private lab..."
PTL is mentioned as a company that does emissions testing. The speaker thinks labs like PTL could play a bigger role in how trucks prove they meet pollution rules.
PTL is referenced as a private emissions-testing lab that the speaker believes represents the future of emissions verification. The context suggests the industry may rely more on specialized labs rather than only traditional channels.
2012 standards
"...go to to say 2012 standards, which modern trucks can pass without emissions."
“2012 standards” are rules about how much pollution a vehicle is allowed to produce. The point here is that newer trucks may already be able to meet those older limits.
“2012 standards” refers to a regulatory emissions benchmark that vehicles must meet. The speaker is arguing that modern diesel trucks can comply with these older limits, which would affect what future standards should look like.
federal requirements
"...do their own self testing and meet the the federal requirements. Because at the end of the day, that's really all that should happen."
Federal requirements are the official U.S. rules that products have to meet. The speaker is saying the testing should prove the product meets those rules.
“Federal requirements” here refers to U.S. regulatory standards that diesel equipment and emissions-related hardware/software must comply with. The key point is that the testing and documentation are meant to show compliance with those rules.
good faith reasonable testing
"...that's good faith reasonable testing is to be able to meet like an FTP 75 store all the records."
This is basically the idea that you should test things in a responsible way that makes sense for proving you follow the rules. Instead of guessing, you run tests that can stand up if regulators or customers ask for proof.
“Good faith reasonable testing” describes an approach where a company performs testing that is appropriate and defensible to demonstrate compliance with regulations. In practice, it means doing enough real-world or standardized testing to support claims, rather than relying on assumptions.
FTP 75
"...good faith reasonable testing is to be able to meet like an FTP 75 store all the records. And if anybody asks you about it later, show them your data."
FTP 75 is a standardized driving test the government uses to check emissions and fuel economy. If a company says they meet FTP 75, it means their setup performed well on that official test, and they should be able to prove it with the test data.
FTP 75 refers to the U.S. Environmental Protection Agency’s “Federal Test Procedure” used to measure emissions and fuel economy under standardized driving cycles. When someone says a vehicle or calibration must meet FTP 75 store/all the records, they’re talking about passing those official test results so the data can be shown if questioned later.
exhaust manufacturer
"[1187.5s] companies, right? There was a [1188.6s] lot of shift in exhaust [1190.7s] manufacturer EGR [1191.8s] manufacturer. And like you"
They’re talking about the companies that make exhaust-related parts for diesel vehicles. If the supplier changes, the parts can be better or worse, which can affect how well the truck runs and how long the parts last. It can also affect emissions equipment performance.
“Exhaust manufacturer” here likely refers to companies producing exhaust-related components (such as emissions hardware, exhaust systems, or related parts) used in diesel applications. The speaker’s point is that there’s been a shift in who supplies these components, which can change fitment, durability, and emissions behavior. It’s relevant because exhaust hardware quality can strongly affect long-term reliability.
EGR
"[1187.5s] companies, right? There was a [1188.6s] lot of shift in exhaust [1190.7s] manufacturer EGR [1191.8s] manufacturer. And like you"
EGR is a system that sends some exhaust gas back into the engine. That helps the engine burn cleaner by lowering the heat during combustion. Some tuning companies change how EGR works, which can change how the truck drives.
EGR stands for Exhaust Gas Recirculation. It routes a portion of exhaust gas back into the engine to reduce combustion temperatures and lower NOx emissions. Diesel tuners and manufacturers often adjust EGR behavior because it can affect drivability, soot, and emissions compliance.
emissions transparency / "who's doing what" in applications
"[1203.0s] no validity. There's no, there's [1204.5s] no transparency on who's [1208.9s] doing what in some of [1210.8s] these in some of these [1212.4s] applications, right? You"
They’re talking about not knowing who made the parts or who set up the software/calibration for certain diesel applications. If that information isn’t clear, it’s harder to judge quality and harder to fix problems later. It can also make it tough to know what’s compliant versus not.
The speaker is describing a lack of transparency in the diesel parts/software ecosystem—who actually manufactures components and who calibrates/tunes them for specific applications. In practice, this matters because quality and performance can vary widely when supply chains and calibrations aren’t clearly documented. It also affects troubleshooting and warranty/legality considerations.
diesel automotive tuning ecosystem (Facebook groups / paid advertising / algorithm)
"[1213.4s] you could go on any, any [1216.3s] Facebook group, and you could [1218.5s] go and see paid advertising, [1220.0s] right? If you get into the [1220.9s] algorithm of diesel [1222.2s] automotive, and there's a [1223.8s] lot of shit out there"
They’re describing how diesel tuning stuff gets promoted and found online—ads, social groups, and algorithms. That means you can run into a lot of sellers, not all of them equally trustworthy. It’s a reminder to research carefully before buying.
The speaker references how diesel tuning products are marketed and discovered through social platforms and algorithms, including paid ads and community groups. This highlights how buyers can be exposed to many vendors with uneven reputations, making it harder to verify quality and technical claims. For enthusiasts, it underscores the value of vetting vendors and asking for documentation.
low-quality aftermarket tunes/parts causing mechanical problems
"they're going into other mechanical problems, because the tune they put on their truck or the parts they put on their truck are real low grade to begin with."
They’re basically saying cheap or mismatched upgrades can create new problems after the truck starts acting weird. If the tune and parts don’t match the engine’s real limits, the truck can end up needing repairs.
The hosts are describing a common diesel-performance failure mode: budget or mismatched aftermarket tunes and parts can lead to “secondary” mechanical issues after initial drivability problems. This often happens when fueling/boost targets exceed what the supporting hardware, cooling, and engine condition can safely handle.
tune library
"they get a tune library, right and freaking buy a tune library out of China or whatever for 200, 250 bucks."
A “tune library” is a set of pre-made computer settings for trucks. If the file doesn’t match your exact truck and parts, it can cause trouble instead of helping.
A “tune library” refers to pre-made ECU calibration files sold as a package, often intended for specific engine/vehicle combinations. The risk is that a generic or poorly matched file may not account for the truck’s exact hardware, emissions equipment, or mechanical condition.
buying tunes from overseas/low-cost sources
"buy a tune library out of China or whatever for 200, 250 bucks. And they'll"
They’re warning about buying cheap engine computer tunes from unknown sellers. If the tune isn’t well tested for your exact truck, it can lead to reliability problems.
The segment highlights the practice of purchasing inexpensive tunes from overseas sources. From an ownership standpoint, low-cost tunes can be less tested, may not be properly calibrated for the specific engine hardware, and can increase the chance of drivability issues or component stress.
aftermarket diesel tuning marketing/labeling
"what I've noticed is like they're putting labels like Duramax tuner, motor ops, PPI, they're putting all these labels on tunes that do not belong to any of us. And it's like that but what's marketing now"
They’re talking about tunes being sold with labels that may not be accurate. That’s important because the “right” tune for the truck can be very different from a tune that’s just copied or misrepresented.
The host is describing a problem where aftermarket diesel tunes are being mislabeled or marketed under names that don’t match the actual origin or quality. This matters because tune authorship and calibration intent affect compatibility, safety, and performance outcomes.
motor ops
"they're putting labels like Duramax tuner, motor ops, PPI, they're putting all these labels on tunes that do not belong to any of us"
“Motor Ops” sounds like a company name tied to diesel tuning. The speaker is saying some products are being labeled like they’re from that source when they might not be.
“Motor Ops” appears to be a brand or label used for diesel tuning products. In the context of the discussion, the host is criticizing tunes being marketed under certain names even when they may not be from the intended source.
industry going back to 2006/2007 tuning quality
"because of what the government's done and hurt the American company so bad. This industry is going back to what feels like 2006. 2007. As far as like the tuning ask quality."
They’re saying the diesel tuning scene feels like it did back in 2006–2007. The point is that tune quality and reliability may not be as good as it used to be.
The speaker claims the diesel tuning industry is regressing to an earlier era (around 2006–2007) in terms of tuning quality. That implies a shift in standards, customer expectations, or product consistency—often tied to changes in regulations, emissions equipment, and the availability of reputable calibrators.
pro mod level race cars
"outside of, you [1302.8s] know, basically pro mod level [1304.6s] race cars, like, man, we [1306.3s] haven't been able to see a [1307.6s] ton of a ton of a ton of"
Pro mod is a very serious drag racing category with highly modified cars. The speaker is saying that race cars get new tech faster than normal street trucks do.
“Pro mod” is a top-tier drag racing class where cars are heavily modified for maximum performance. The comparison here suggests that while extreme race platforms see rapid development, street-oriented diesel trucks haven’t seen the same pace of new systems.
turbo chargers
"outside of like some of the [1312.4s] cool turbo chargers and [1313.6s] stuff you guys do. Like there [1315.5s] hasn't been like this big [1316.7s] advancement for what we [1318.5s] would call like the street"
A turbocharger uses exhaust gases to spin a compressor that pushes more air into the engine. More air can mean more power, but it also needs good tuning to avoid overheating or stress.
Turbochargers force more air into the engine, allowing more fuel to be burned efficiently for higher power—especially on diesels. In performance builds, turbo choice and boost control strongly influence spool time, heat management, and overall reliability.
street style trucks
"outside of like some of the [1312.4s] cool turbo chargers and [1313.6s] stuff you guys do. Like there [1315.5s] hasn't been like this big [1316.7s] advancement for what we [1318.5s] would call like the street [1319.6s] style trucks."
“Street style trucks” are diesel performance builds intended for everyday driving rather than purpose-built drag or pro-mod racing. The tradeoff is that they need to balance power with reliability, emissions equipment, and drivability—so innovation often happens more slowly than in extreme race applications.
calibrated power
"there was some fun banter [1326.3s] 2013-2014 between, you know, [1331.0s] PPI, calibrated power, [1332.8s] motor ops, right?"
“Calibrated power” means the truck’s computer is tuned to make a certain kind of power. That tuning changes how much fuel and boost the engine uses.
“Calibrated power” refers to power output that’s achieved through tuning and calibration of the engine control unit (ECU). In diesel trucks, small changes to fueling, boost targets, and timing can significantly affect drivability and performance.
DIY guys going on the forums, putting different tunes in their truck
"There was a [1334.3s] lot of fun DIY guys going [1337.4s] on the forums, putting [1338.8s] different tunes in their [1339.7s] truck, going to the track"
The segment is talking about people modifying their trucks themselves by loading different software “tunes.” Tunes can make the truck feel faster, but they can also stress the engine if the truck isn’t set up or monitored properly.
This describes the common diesel-performance culture of using aftermarket tuning (“tunes”) shared and discussed in online forums. Different tunes can change fueling and boost behavior, which can improve performance but also increases the importance of monitoring EGTs, boost, and supporting hardware.
diesel performance industry future
"and that innovated. Like that pushed us... then what happened? That truck ended up being like one of the fastest LMLs because you had companies passionate about their work competing as you're supposed to when"
They’re talking about where the diesel performance world is headed. The idea is that racing and people building faster trucks help drive new improvements over time.
The hosts are discussing how competition and innovation in the diesel performance world push technology forward. This kind of “industry future” talk often centers on how manufacturers, tuners, and racers respond to rules, emissions, and customer demand.
Hyundai Kona
"online name back in the day was like Kona or something like that. And he had a 2011"
The Hyundai Kona is a small SUV meant for regular commuting and errands. It’s built to be practical and easy to live with, and depending on the year and market it may come with different engine options. The podcast’s “2011” reference may be pointing to an older Hyundai model or a name mix-up.
The Hyundai Kona is a compact crossover SUV designed for everyday driving, with options that can include gasoline and, in some markets/years, diesel or other powertrains. It comes up in conversations because owners often discuss real-world reliability, maintenance costs, and how it performs in daily use. The mention of a “2011” in the podcast context suggests the discussion may be about an older Hyundai model or a mix-up with the Kona name from that era.
two tints at the track
"And he had a 2011 or 2012 LML and the fights we were having back then was over literally two tints at the track."
They’re describing a super small difference in how fast the truck was at the track. Even a little change in setup or tuning can swing results when the competition is that close.
“Two tints” is a slang way of describing a very small performance gap on track—essentially a tiny difference in elapsed time or distance. In diesel performance circles, that kind of margin can come down to tuning, traction, and how consistently the truck makes power under load.
bang limiter
"bang limiter? Like, what are we doing? What did I go wrong? And we get calls with AI like, oh, what's injectors and pumps should I run?"
A “bang limiter” is a safety/tuning feature that helps stop the engine from firing too violently. It’s there to keep combustion from getting harsh and potentially damaging parts.
A “bang limiter” is a control strategy used on diesel engines to prevent harsh combustion events—often described as limiting how aggressively fuel is delivered or how quickly cylinder pressure rises. In practice, it’s meant to reduce clatter/knock and protect components when tuning or running aggressive setups.
AI-generated parts recommendations can be wrong
"And we get calls with AI like, oh, what's injectors and pumps should I run? ... And it was, it was fucking crazy. It gave him part numbers and stuff. And the part numbers were wrong."
The host is warning that AI advice about car parts can sound confident but still be wrong. With diesel trucks, the exact engine setup matters, so you should verify part numbers with a real fitment guide or shop.
The segment highlights a real-world risk: AI can generate plausible injector/pump/turbo/intake recommendations and even list part numbers, but those outputs may be incorrect for the specific engine, year, or configuration. In diesel builds, compatibility and calibration details are crucial, so wrong parts numbers can lead to wasted money or unsafe fueling.
injectors
"And we get calls with AI like, oh, what's injectors and pumps should I run? And I remember you had one because you're on speaker phone."
Injectors are the parts that spray fuel into the engine. If you swap or tune injectors without matching the rest of the fuel system, you can get poor performance or even damage.
Diesel injectors meter fuel into the combustion chamber at precise times and pressures. In performance tuning, injector choice (flow rate, calibration, and sometimes nozzle design) must match the engine’s fueling strategy and supporting hardware like the high-pressure pump and turbo.
pumps
"And we get calls with AI like, oh, what's injectors and pumps should I run? And I remember you had one because you're on speaker phone."
In a diesel, pumps move fuel and build the pressure needed for the injectors to spray correctly. Choosing the wrong pump for your setup can cause fueling problems and reliability issues.
“Pumps” in diesel performance usually refers to the high-pressure fuel pump (and sometimes the lift pump) that supplies fuel pressure for injection. Correct pump selection is critical because injector operation depends on the pressure and delivery characteristics the pump can provide.
intake
"He's like, AI told me on my 18 ram like this is the turbo. This is the intake this, this, this and this."
The intake is how air gets into the engine. If you change the intake, the engine may need tuning so it knows the new airflow and can fuel and run smoothly.
In diesel performance, “intake” typically means the air intake system (airbox, piping, filters, and sometimes intercooler plumbing) that delivers charge air to the engine. Intake changes affect airflow and pressure readings, which can require tuning to avoid drivability issues or incorrect fueling.
dyno
"...operating off of theories when we operate off of real world conditions in the dyno that as we both know..."
A dyno is like a treadmill for a vehicle’s drivetrain. It lets you measure power in a controlled setting, but real driving can feel different than what the dyno predicts.
A dyno is a test stand that measures how much power and torque an engine makes under controlled conditions. Diesel tuners often use dyno results to estimate real-world performance, but the numbers can shift when the truck is driven on real roads.
real-world conditions
"...it's not going to be on it's going to be operating off of theories when we operate off of real world conditions in the dyno..."
“Real-world conditions” refers to how a truck performs in everyday driving—road load, temperatures, traction, and driver inputs. The point here is that dyno predictions based on theory can miss what happens when the vehicle is actually used.
horsepower
"...say this is probably going to make a hundred horsepower and it's going to be within 20 horsepower up or down..."
Horsepower is a number that describes how strong an engine is. Higher horsepower usually means more pull, but how it feels day-to-day also depends on other factors like torque.
Horsepower is a measure of engine output—how much work the engine can do over time. In tuning discussions, people use horsepower to compare setups, but it’s only one part of the story; torque and drivability matter too.
EPA fight
"And we'll go back onto the like the whole EPA fight side of things, like what what is the end game? Like what's what's the end goal here?"
When people say “EPA fight,” they mean arguments over air-pollution rules in the U.S. The EPA sets limits on what vehicles can emit, and diesel companies and enthusiasts often disagree about how those rules should be followed.
The “EPA fight” refers to disputes and regulatory pressure involving the U.S. Environmental Protection Agency (EPA). In diesel performance, it often centers on emissions rules, compliance strategies, and how manufacturers or tuners handle real-world pollutants like NOx and particulate matter.
end goal
"like what what is the end game? Like what's what's the end goal here? Is it that I"
They’re asking what the final target is—what everyone is trying to achieve after all the rule changes and arguments. In diesel terms, it usually means vehicles can be made to pass emissions rules without ruining how they drive or how easy they are to maintain.
“End goal” here is about the intended outcome of emissions regulation and industry responses—what success looks like after the current conflicts. For diesel, that typically means meeting legal emissions limits while still allowing practical drivability and serviceability.
legally delete my truck
"[1561.4s] can legally delete my truck? [1563.0s] Is it that there is a"
“Deleting” a diesel truck generally means removing or turning off emissions equipment. The legality depends on local laws and whether the truck still has to meet emissions requirements.
“Deleting” a diesel truck usually refers to removing or disabling emissions-control hardware (like EGR/DPF/DEF-related systems) and/or altering software to bypass emissions testing. Whether it’s legal depends on federal and state rules, the truck’s emissions compliance status, and how enforcement is handled.
timeline of a vehicle depending on an age
"Is it that there is a [1564.8s] timeline of a vehicle [1566.7s] depending on an age that, [1568.6s] you know, they're no longer"
The speaker is referencing that emissions obligations can change based on a vehicle’s age or compliance timeline. In practice, rules may differ for newer vehicles versus older ones, and enforcement or required equipment can vary accordingly.
manufacturers have to retool and retest
"So the thing is, [1593.4s] is people say or a big dilemma [1595.2s] would be, well, the [1596.5s] manufacturers have to retool [1598.2s] the manufacturers have to [1599.2s] retest, like they don't [1601.2s] there, it's going to take"
When the rules change, car makers may need to update their manufacturing process and prove the new design still meets emissions standards. That takes time and testing before it’s approved.
When emissions regulations change, manufacturers often must redesign (“retool”) production and validate (“retest”) that engines still meet the new standards. This is a major reason regulatory transitions take time and can affect model availability and compliance strategies.
calibrations
"The manufacturer already has those calibrations. They already have the tuning."
Calibrations are the computer settings that tell the diesel engine how to run. They also help the emissions system do its job correctly, depending on things like temperature and driving load.
Calibrations are the software settings used to control how an engine and emissions systems operate. They determine fuel delivery, boost, and how the aftertreatment hardware is managed so the vehicle meets emissions standards under different conditions.
after treatment system
"The ports are that's way easier to make than, you know, a freaking big after treatment system. So one would be tooling for manufacturers."
Aftertreatment is the “clean-up” equipment on a diesel after the exhaust leaves the engine. It helps the car meet emissions rules by trapping soot and reducing harmful gases, and it has to be set up just right to work well.
An aftertreatment system is the set of emissions-control hardware placed after the engine to reduce pollutants like NOx and soot. On diesel vehicles, it often includes components such as a diesel particulate filter and NOx-reducing systems, and it requires careful calibration to work correctly.
deleted trucks
"Well, the thing is, is deleted trucks past small. They just don't pass readiness monitors."
A “deleted” diesel truck usually means the emissions system was taken out or turned off. People do it for power or to avoid emissions limits, but it can make the truck fail emissions checks and get in trouble with enforcement.
“Deleted trucks” refers to diesel vehicles that have had emissions equipment removed or disabled, typically to reduce restrictions and improve performance or sound. This often changes how the truck behaves during emissions-related checks and can affect compliance with local and federal rules.
readiness monitors
"They just don't pass readiness monitors. So if you come back and say local enforcement, which is really how it should be..."
Readiness monitors are part of a vehicle’s onboard diagnostics (OBD) that track whether emissions-related systems have run their self-tests. If a diesel has emissions equipment removed/disabled, those monitors may never complete, which can cause it to fail inspection even if it runs normally.
local enforcement
"So if you come back and say local enforcement, which is really how it should be, but you come down and, you know, maybe it's a federal thing..."
This means whether emissions rules are enforced depends on local authorities. Even if the rules are federal, what happens to a truck can vary depending on where you live and who’s doing the inspections.
“Local enforcement” refers to how emissions compliance is often handled by local agencies or inspectors, even when rules are federal. The discussion suggests a system where local authorities have discretion, which can lead to inconsistent outcomes for modified/deleted diesel trucks.
THC laws
"maybe it's a federal thing, you know, take it, take it kind of like the THC laws, for example, it's like, well, the government says that this is how it goes..."
They’re comparing this to another set of laws where the rules are the same on paper, but enforcement can differ by location. The point is that “what the government allows” and “what cops/inspectors actually do” aren’t always identical.
The speaker is using “THC laws” as an example of how regulations can be written at a higher level but enforcement can vary locally. In practice, this highlights the difference between what the law says and how agencies choose to enforce it.
inspection sticker
"...for someone to get an inspection sticker, they need to be able to have their vehicle past smog."
An inspection sticker is a tag that shows your car passed the required checks to be street-legal. Usually that includes an emissions test.
An inspection sticker is proof your vehicle passed the required emissions/safety inspection for legal operation. In many areas, passing emissions testing is a prerequisite to receive or renew that sticker.
smog test
"...they need to be able to have their vehicle past smog... like that's a very basic test."
A smog test checks how clean your car’s exhaust is. If it’s too dirty, the car won’t pass and you can’t get the sticker.
A smog test measures how much pollution a vehicle produces, typically by sampling exhaust gases. Depending on the region, it may include tailpipe measurements and checks of onboard emissions systems.
tailpipe sniffer
"...in just regards to the tailpipe sniffer, not the readiness monitors..."
A tailpipe sniffer is the machine that samples what comes out of your exhaust. If your car is running dirty, the numbers can be too high and it won’t pass.
A tailpipe sniffer is the device used to measure exhaust gases during an emissions test. It looks at pollutants in the exhaust, so issues like poor combustion or faulty emissions components can cause a fail.
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