Marcus Grönholm's latest rallying project
About this episode
Marcus Grönholm’s latest rallying project takes center stage as he explains GRD Motorsports’ ARC2: a cost-effective alternative aimed at Rally Two-level pace. He describes early shakedown checks, then first gravel runs in the US, focusing on steering balance, engine mapping, and—above all—reliability so the team can actually run. The hosts also connect rally’s growth in America to possible WRC expansion, discuss fan-friendly “park expose” formats, and debate how regulations and powertrain shifts could reshape rally and rallycross.
Two-time World Rally champion Marcus Grönholm joins SPIN, The Rally Pod for a special episode talking about his work developing JRD Motorsport's new ARC2 car, designed as a cost-effective alternative to Rally2 in America. 'Bosse' also offers his views on the current WRC, explains why his team isn't in rallycross anymore and provides an update on what life looks like in 2026
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Rally2
"Johan Ragnarsson came up with the idea to build a rally car, which could be a rally two level and compete with that car in US and built in US."
Rally2 is a category of rally race cars with rules about what the car is allowed to be. The ARC2 is being built to compete against that kind of race car, but at a lower cost.
Rally2 refers to a specific FIA rally car class (often called Rally2-spec) used in many national and international events. The speaker frames the ARC2 as a cheaper alternative intended to compete against Rally2 cars in the US.
GRD Motorsports ARC2
"So as you say, it's a car built by GRD Motorsports called the ARC2, isn't it, which is meant to be effectively a cost effective alternative to the rally two cars that we see there."
The ARC2 is a rally car project GRD Motorsports is building. Marcus says he tested it and found it was already working well, with only minor tweaks needed before the next test.
The GRD Motorsports ARC2 is a rally car being developed as a cost-effective alternative to Rally2-spec cars. In this segment, Marcus Grönholm describes testing it in the US and notes that only small changes were needed after an initial proper test.
proper test
"No, impression was that we had absolutely no problem with the car first time in a proper test. So everything was working."
A “proper test” means a real, planned driving session to check how the car behaves. Marcus is saying the ARC2 worked well right away during that first serious test.
A “proper test” in motorsport usually means a structured evaluation session where the car is driven under planned conditions to verify baseline setup and performance. Marcus uses it to emphasize that the ARC2 had no major issues on the first real test run.
rally development test
"for those listing that maybe haven't ever been to a rally development test, if you can just explain a guess why you do it and what kind of things you work through on a typical testing."
A rally development test is when the team takes a rally car out to learn how it behaves and to improve it. They try it on the real road surface (like gravel) and adjust the setup so it’s easier and faster to drive.
A rally development test is an organized session where a team evaluates a rally car’s behavior and makes setup changes before (or during) its competitive development. The goal is to learn how the car responds on the specific surfaces—like gravel—and then refine things like balance, steering feel, and power delivery.
shakedown test
"Okay, this was a completely new car out of the box. [276.2s] Okay, they did some shakedown test, just driving around the workshop or something like that."
A shakedown test is an early test to make sure a brand-new rally car is working correctly. It’s like a first check before the team pushes it harder on the actual gravel or stage roads.
A shakedown test is an early, low-risk check of a newly built rally car to confirm basic systems work and to catch issues before more aggressive testing. It often starts with controlled driving (sometimes around the workshop) before moving to the real stage surfaces.
gravel road
"But now we were first time out on the gravel road. [286.2s] So of course, you test the first feeling."
Gravel is a tricky rally surface because the tires don’t grip the same way all the time. Testing on gravel helps the team understand how the car will handle on real stages.
In rallying, gravel road testing matters because the surface changes grip constantly as tires move stones and compacted layers. That makes traction and car balance—how the car behaves when you turn—especially important to evaluate early.
oversteering or understeering
"How does it, you know, had the handling, how steering in and not oversteering or understeering? [299.1s] The car was in good balance."
These terms describe turning behavior. Understeer is when the car feels like it won’t turn enough and pushes outward; oversteer is when the rear feels like it wants to slide out.
Oversteer and understeer describe how a car responds in a turn when grip is limited. Oversteer means the rear tends to step out (rotate more than expected), while understeer means the car pushes wide and won’t turn in as much as you want.
shocks
"So, so now, now, and then we worked on more of engine mappings, shocks, not so much on the [310.1s] diff this time, but next test, yes."
Shocks are what control how the suspension moves over bumps. Tuning them can make the car feel more stable and easier to control on rough rally roads.
Shocks (shock absorbers) control how the suspension moves over bumps and during cornering, affecting ride control and tire contact. In rally testing, adjusting shocks helps the car stay stable and predictable on rough surfaces.
engine mappings
"we worked on more of engine mappings, shocks, not so much on the [310.1s] diff this time, but next test, yes."
Engine mapping is how the car’s computer decides what to do when you press the gas. Tuning it can make the power delivery smoother and easier to control on slippery gravel.
Engine mapping is the calibration of how the engine responds—such as throttle-to-fuel and throttle-to-ignition behavior—across different speeds and loads. In rally development, changing mappings can improve drivability, traction, and how smoothly the car delivers power.
diff
"we worked on more of engine mappings, shocks, not so much on the [310.1s] diff this time, but next test, yes."
The diff is the part that controls how power goes to the two driven wheels. On rally cars, it can be tuned to help the car grip better and stay stable on loose surfaces.
The diff (differential) sends power to the left and right wheels while allowing them to rotate at different speeds in turns. Rally teams may adjust differential behavior to manage traction and stability, especially when the surface is loose.
rally two
"But can you feel that this car has the potential to, I guess, achieve its objective of being at rally two performance? ... You can take 360 horsepower out of it, but we are going down because we, they want to go like a rally two cars level with them."
“Rally Two” is a rules/class level in rallying. The team is building the car to match the kind of specs and performance that cars in that class are expected to have.
“Rally Two” refers to a rally competition class/regulation level that sets expectations for car specs and performance. When the hosts say they’re aiming to be “at rally two cars level,” they mean the build is being tuned to match what that class typically allows and what it needs to be competitive.
horsepower
"It should be 360. You can take 360 horsepower out of it, but we are going down because we, they want to go like a rally two cars level with them."
Horsepower is a way to measure how strong the engine’s output is. More horsepower usually means more potential speed, but rally teams also have to keep the engine reliable for long stage runs.
Horsepower is an engineering measure of how much power an engine produces. In rally builds, targeting a specific horsepower number is about balancing speed with reliability and rule compliance for the class they’re aiming at.
gearbox
"So yeah, and there are good shock absorbers, gearbox seems to work. Yeah, things to do still, but the good beginning, good start."
The gearbox is what helps the engine deliver power in the right way for different speeds. In rallying, it matters for getting good acceleration and keeping the car controllable.
A gearbox is the transmission’s gear set that changes engine speed to match driving conditions. In rally cars, gearbox behavior affects acceleration out of corners and how smoothly the car can be driven across varying stage surfaces.
shock absorbers
"And yeah, it's, it looks and sound good. So yeah, and there are good shock absorbers, gearbox seems to work. Yeah, things to do still, but the good beginning, good start."
Shock absorbers help the car handle bumps. In rally driving, they’re important because they keep the wheels working well on uneven roads.
Shock absorbers (dampers) control how the car reacts to bumps and impacts by managing suspension movement. In rallying, good dampers help keep the tires in contact with the road over rough stages, improving traction and driver confidence.
park expose concept
"And really there were some aspects of that that you really, really liked, particularly this park expose concept they've got where all the cars line up with the fans before each day of, of rallying."
Rally events often have a public viewing area where the cars are parked and fans can walk around and look at them. It happens before the racing stages so people can see the cars up close.
In rallying, a "park expose" (often called a fan park or public viewing area) is an organized setup where the cars are displayed to spectators before the stages. It’s designed to let fans get close to the rally cars, see teams and drivers, and build excitement ahead of competition.
Formula One
"maybe Formula One now. And that's what we need to do as a sport is bring them to rallying because we all know it's the best."
Formula One is the top level of open-wheel racing, with very advanced cars and races around the world. The host is saying the U.S. already watches F1, so rallying might be able to attract fans too.
Formula One (F1) is the highest tier of open-wheel circuit racing, known for highly engineered cars, strict technical regulations, and global race calendars. The host’s point is that if the U.S. already follows F1, rallying could gain traction by offering a similarly high-profile international spectacle.
IndyCar
"yeah, Americans, they, they, they love, you know, NASCAR and these IndyCars, but this is a completely different thing."
IndyCar is a major American open-wheel racing series, best known for oval and road-course events. The host contrasts it with rallying to explain that rally needs different fan conversion than the mainstream U.S. motorsports ladder.
NASCAR
"yeah, Americans, they, they, they love, you know, NASCAR and these IndyCars, but this is a completely different thing."
NASCAR is a very popular kind of racing in the U.S. It uses stock cars and is usually run on oval tracks. The host is contrasting it with rallying to explain why rally has to grow its audience.
NASCAR is a major American stock-car racing series, typically raced on oval tracks with close, contact-heavy racing. Mentioning NASCAR highlights the cultural difference the host is talking about—rallying has to compete for attention in a market dominated by other motorsport formats.
WRC event
"Do you think having a WRC event there will make a difference? Obviously, that is the intention for, for next year subject to all the FIA pre was going correctly."
WRC means the World Rally Championship, which is the biggest rally racing series. If a WRC race happens in a new place, it can help more people pay attention to rallying.
WRC stands for World Rally Championship, the top level of rally racing run by the FIA. A WRC event in a new country is often used to grow local interest because it brings the sport’s highest-profile teams and drivers to local fans.
FIA
"Obviously, that is the intention for, for next year subject to all the FIA pre was going correctly."
The FIA is the main organization that sets the rules for big international racing. They have to approve and oversee events so everything meets the sport’s regulations.
The FIA (Fédération Internationale de l’Automobile) is the governing body that oversees major motorsport rules and championships, including the World Rally Championship. When the hosts mention FIA requirements “going correctly,” they’re referring to the sanctioning and regulatory approvals needed for an event to happen.
ARC2 car
"Okay. And back to the ARC2 car for me, because the question has just popped into my mind."
ARC2 is a category of rally cars that compete under a shared set of rules. The discussion is moving from general rallying to what kind of car fits that category.
ARC2 refers to a rally competition class (often discussed in the context of the FIA rally pyramid) for cars built to specific technical rules. When the host says “back to the ARC2 car,” they’re shifting from the broader rally discussion to the specific class and its eligible car platform.
puncture change
"This time, unfortunately, for Sebastian OJ, it was a puncture change that meant he dropped from first to sixth."
That phrase means the driver had a tire puncture and had to change the wheel quickly. In rally racing, losing time like that can cost you big places in the standings.
A “puncture change” refers to the rapid response to a punctured tire during a rally—typically swapping to a spare wheel/tire and getting back on course. In rallying, even a short delay can drop a driver many positions because stages are run back-to-back.
Hyundai
"I think it was perfect and really nice that Hyundai won because they need it. They have been so low now with the results and everything."
Hyundai is the car brand behind the rally team they’re talking about. When Hyundai wins, it’s a big deal for the team because it proves their rally cars and setup are working.
Hyundai is referenced here as the manufacturer/team that won the rally. In WRC, manufacturer wins are important because they reflect the competitiveness of the whole rally program, not just one driver.
Toyota
"Toyota had taken everything, so it's also for the sport is very important. So it was good."
Toyota is another car brand in the rally series. They’re saying Toyota had been winning a lot, and Hyundai’s win helps create a closer competition.
Toyota is mentioned as the dominant force earlier in the season (“took everything”), setting up the competitive contrast with Hyundai. The discussion highlights how manufacturer performance affects the overall fight in the championship.
Chevrolet Monte Carlo
"... if you remember when also when Ljub came back to Monte Carlo with a Ford, he won and he was 48 or something."
The Chevrolet Monte Carlo is a type of older American coupe. In this podcast, “Monte Carlo” is also the name of a place/event, so it comes up when they’re talking about a past race result. The car name is being used in that story context.
The Chevrolet Monte Carlo is a classic American personal luxury/pony-style coupe that became especially well known in rally and motorsport stories from the era when touring cars and coupes were common. It’s mentioned here because the podcast is recalling a past win in Monte Carlo involving a Ford, and the name “Monte Carlo” is being used as a shorthand for that location and era of competition. That makes it a relevant reference point for listeners who remember the kinds of cars that were prominent around those events.
electric vs internal combustion in motorsport
"electric behind and going back to internal combustion? ... First, it was a big, big, you know, wow everybody, we have to go to electric now ... then they stopped everything with electric"
They’re talking about switching racing cars from gas engines to electric power. The big issue is whether teams can afford it and support it long-term.
The discussion contrasts electric powertrains with internal combustion engines (ICE) in motorsport. It also touches on how rule changes and cost can affect whether teams can realistically compete in an “electric now” era.
world championship vs European championship
"And then they stopped everything with electric and now there is no world championship anymore ... Now it's European championship."
They’re comparing racing at a worldwide level versus a Europe-only level. They’re also saying the smaller series can be harder for sponsors to justify.
They’re comparing a global “world championship” format to a regional “European championship” format. The hosts connect the change to commercial realities like sponsor interest and the overall visibility of the series.
Volvo CE
"I was not ready to start a new team after four years with Volvo CE."
Volvo CE is part of Volvo that makes construction equipment. The speaker is saying they weren’t ready to leave that situation to rebuild a racing team.
Volvo CE is Volvo’s construction-equipment business, and the speaker mentions it as the employer context before deciding not to start a new rally team. The point is about career timing and the effort required to rebuild a team from scratch.
alternative power solutions
"Because I guess we all need to be thinking about alternative power solutions as motorsport."
They mean other ways to power racing cars besides the usual gas engine. That could include electric or hybrid-style setups.
“Alternative power solutions” refers to non-traditional ways of powering vehicles, such as electric drivetrains, hybrid systems, or other low-emissions technologies. In motorsport, it’s a broad umbrella for how teams adapt to changing energy and emissions expectations.
combustion rather than electric
"But do you think it's the right thing that we've gone back to combustion rather than electric? Yeah, I think so."
They’re talking about whether rally cars should use regular fuel engines again instead of electric motors. That choice changes how the cars are built and how the competition rules have to work.
The hosts are debating whether rally should return to internal-combustion powertrains instead of going fully electric. In motorsport, this affects vehicle weight, energy management, sound/feel, and how rules are written for performance and reliability.
rallycross
"after when the new rally cars, the plan was that 27 rally cars would go into rallycross and mix them somehow, I don't know. ... WRC and hopefully WorldRX, either way rallycross to share the same platform of car, which is different,"
Rallycross is a racing event where rally-style cars race on a track that’s usually shorter and more mixed-surface than a traditional rally stage. This segment is about connecting rallycross with the WRC rules.
Rallycross is a motorsport format that typically mixes rally-style cars with a short, closed-circuit course that includes both tarmac and gravel sections. The discussion here is about how rallycross and WRC could align rules and car platforms.
WorldRX
"And as you said there, that the plan is for, I guess, WRC and hopefully WorldRX, either way rallycross to share the same platform of car, which is different,"
WorldRX is the top rallycross championship. The hosts are saying it could be aligned with WRC so the cars and rules are more similar.
WorldRX refers to the FIA World Rallycross Championship branding. In this segment, it’s mentioned alongside WRC as part of a plan to align rules and car platforms between the two championships.
share the same platform of car
"either way rallycross to share the same platform of car, which is different, Isn't it? I know we've seen that rallycross cars are similar-ish to rally cars."
They mean using a similar base car design for both rally and rallycross. The goal is to make it cheaper and simpler for teams to move between the two competitions.
“Sharing the same platform” means using a common underlying car architecture and rules baseline across different championships. In rally and rallycross, that typically aims to reduce development cost and make it easier for teams to compete in both series.
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