Every Memorial Day weekend, thirty-three cars line up at Indianapolis Motor Speedway for the most famous race in American motorsport. Every single one of those cars is powered by an engine built by one of two companies. Either Chevrolet or Honda. That is it.
Two manufacturers, one race that has been running for over a century, and a situation that a lot of people accept without ever wondering how it got there.
The answer involves an eleven-year civil war that nearly destroyed American open-wheel racing entirely, a bankruptcy, a Japanese manufacturer walking out the door to join NASCAR, and a solo supplier arrangement that sat like a warning sign for half a decade before someone finally came back to compete.
The story of why only Chevy and Honda supply the Indy 500 is actually the story of how the sport almost ceased to exist as a functioning commercial entity, and the two manufacturers still standing are in many ways the survivors of something that should have killed the whole thing off.
A Split That Lasted Eleven Years and Wrecked Everything It Touched
To understand where IndyCar is now you have to go back to 1994, when a man named Tony George, the president of Indianapolis Motor Speedway, announced he was creating an entirely new racing series called the Indy Racing League.
The existing American open-wheel championship was called CART, the Championship Auto Racing Teams, and it had been the premier series in the country for over a decade with strong manufacturer support, international venues, competitive fields and genuine television interest.
By the mid-1990s it had Ford, Mercedes-Benz, Honda and Toyota all developing engines to compete in it. It was a healthy series with real commercial momentum.
George had a problem with the direction CART was taking the sport. His view was that it had drifted too far from its American roots, spending too much money, racing on too many international circuits, and losing touch with the oval-track identity that made the Indianapolis 500 what it was.
CART tried to trademark the phrase “IndyCar” which George found intolerable since his family owned the Indianapolis Motor Speedway, the track that had given the word its meaning.
He fought back by naming his new series the Indy Racing League and announcing that 25 IRL teams would receive automatic qualifying spots at the Indianapolis 500, leaving CART teams to fight over the remaining eight positions.
The CART teams responded by boycotting the 1996 Indianapolis 500 entirely. The greatest race in American motorsport ran that year without most of its best drivers and teams. The audience noticed. The sponsors noticed. The manufacturers most certainly noticed.
What followed was eleven years of two competing American open-wheel championships existing simultaneously, each draining the other of resources, teams, sponsors and credibility. CART tried to continue racing internationally, eventually filing for bankruptcy in 2003 after losing its title sponsor FedEx and watching both Honda and Toyota defect to the IRL.
The series was bought out of bankruptcy, rebranded as Champ Car World Series, stumbled through a few more seasons and then filed for bankruptcy again in 2007.
The IRL absorbed its remaining teams at the start of 2008, and the unified series that emerged from the wreckage took the name IndyCar, the very name that George had fought CART over a decade earlier.
The damage was enormous and long-lasting. Toyota had joined the IRL but left for NASCAR after the 2007 season, a decision that said everything about where the priorities of a major manufacturer lay when forced to choose between a consolidating IndyCar and a healthy stock car series with a vastly bigger American television audience.
By the time Toyota departed, Honda had become the sole engine supplier to IndyCar from 2006 through 2011, a monopoly arrangement that produced reliable machinery but zero competition between manufacturers and no compelling engine-side narrative for fans to follow.
A racing series with one engine supplier is not really a competition in any meaningful technical sense, and the series looked and felt like a diminished version of what it had once been.
The salvation came in 2011 when IndyCar announced a completely new engine formula designed specifically to attract multiple manufacturers.
The new spec called for a 2.2-liter twin-turbocharged V6 running on 85 percent ethanol fuel, a dramatic departure from the naturally aspirated V8 engines that had defined the IRL era.
The brief, specs were deliberately written to be accessible enough that more than one or two companies could justify the investment.
Chevrolet returned to IndyCar in 2012 after a five-year absence, building its engine through Ilmor Engineering, the company co-founded by Mario Illien and Roger Penske whose Penske Entertainment firm now also owns IndyCar itself.
A British company called Lotus also entered in 2012 under a supply agreement with a small team, but their engine was so far off the pace that cars running it were sometimes thirty miles per hour slower than their Honda and Chevrolet competitors. Lotus departed after a single season and has not returned.
From 2012 onwards, it has been Chevrolet versus Honda. Their rivalry has produced some genuinely competitive seasons.
Chevrolet dominated the first few years of the new formula, winning the manufacturers championship four consecutive times. Honda fought back.
The two manufacturers have evenly split most statistical measures across the fourteen years since Chevrolet’s return, with individual seasons swinging in either direction.
In a spec chassis series where every team runs the same Dallara car, the engine is where manufacturers can actually differentiate themselves, and the competition between the two has been real even if the field has stayed at two.
Why Getting a Third Manufacturer Into IndyCar Is Almost Impossible
The names that IndyCar officials have floated publicly when discussing potential new manufacturers over the past decade read like a fantasy wishlist for any motorsport promoter. Porsche, Audi, Ferrari, Toyota, Hyundai, Lamborghini. All have been mentioned.
Some have been in serious talks. None have committed. Understanding why requires understanding something fundamental about what IndyCar actually is as a commercial proposition for a manufacturer.
IndyCar is a spec series. Every team races the same Dallara chassis, developed by the Italian constructor under long-term contract with the series.
The engine is the only major technical variable available to a manufacturer, which means there is limited scope for a company to demonstrate engineering superiority through aerodynamics, suspension design or chassis construction the way they could in Formula One.
What a manufacturer gets from IndyCar is primarily branding visibility, American market exposure and whatever engineering knowledge transfers from developing a highly specialised racing engine.
Measured against the cost of a competitive IndyCar engine program, which insiders estimate at somewhere between $50 million and $100 million over a multi-year commitment, the return on investment is difficult to justify compared to other racing series.
The television audience problem compounds this. NASCAR has consistently delivered larger American viewing numbers than IndyCar.
Formula One has grown significantly in the United States through the Netflix Drive to Survive effect and now commands premium advertising rates from a young, affluent demographic that manufacturers specifically target.
IndyCar sits in between the two, with a loyal fanbase and strong attendance at marquee events like the Indy 500 but modest viewership for the rest of its calendar.
For a manufacturer running the numbers on where to spend its motorsport budget, IndyCar rarely wins that calculation against its competition.
Honda came dangerously close to walking away in 2023, when the Japanese manufacturer publicly announced it was re-evaluating its IndyCar participation due to rising costs.
The announcement sent a genuine shock through the series because a return to a single-supplier arrangement, or worse, the departure of Honda leaving Chevrolet as the only option, would have been a significant blow to the competitive credibility of the sport.
What saved the relationship was partly the development of the new hybrid power unit, a project where Honda and Chevrolet actually worked closely together with IndyCar on shared components while developing their own distinct hybrid systems around it.
IndyCar president Jay Frye credited the hybrid project with revitalising Honda’s engagement with the series.
“The work we’ve done with Honda this year has been very close as well as with GM,” Frye said. “They seemed very engaged in the series right now.”
In February 2026, both Chevrolet and Honda confirmed extensions that will keep them in IndyCar beyond 2026, covering a gap year in 2027 with the current 2.2-liter engines before switching to entirely new 2.4-liter twin-turbo V6 hybrid units in 2028 alongside Dallara’s next-generation IR28 chassis.
The new formula is being designed explicitly to lower barriers of entry in the hope that a third manufacturer will eventually join.
IndyCar officials have specifically rewritten the engine specifications to make them more attractive to potential entrants by allowing more development freedom and reducing mandated shared components.
Whether Porsche, Toyota or any of the other names on that list ever commits remains to be seen.
What is known is that both Chevy and Honda survived a period of genuine uncertainty about their futures in the series, signed new long-term deals and will be the only two engine manufacturers on the grid when the 110th Indianapolis 500 runs this Sunday on Memorial Day weekend 2026.
Thirty-three cars. Two engines. One hundred and ten years of racing history.
The simplicity of the current arrangement disguises a story that was anything but simple to arrive at, and the two names on those engine covers are there not because the sport chose exclusivity but because the sport barely survived long enough for anyone to still be choosing at all.
