Acura enters the first season of IMSA’s GTP era with its ARX-06 built to LMDh rules, which debut in the Daytona 24 Hours at the end of January, using a 2.4-litre V6 that features a twin-turbo.
Salters said his design team had “a lot of freedom” and took “quite a lot of risk” with the powerplant, which is paired with the first electrical hybrid system in top-class American racing.
When asked to clarify if this engine is the same as the one originally envisaged for the 2024 IndyCar – which had planned to switch to a 2.4-litre motor for its hybridised future but backtracked on the move in mid-December – Salters admitted there is a link between them as they were multiple years in the design process.
“We didn’t know that two years ago, I guess,” he said of IndyCar’s U-turn decision to remain with its 2.2-litre engines for at least the next two seasons.
“There is some commonality. The president has to manage his budget, we’re a racing company that builds our own powertrains, so there has to be some economy of scale – whether it’s through simulation tools, dyno or assembly.
“Being in multiple racing series, it would be pretty silly not to try and combine that to find some efficiency. We’re crazy but not that crazy. There is some commonality – it starts off like that and then it diverges as the mission becomes different.
“HPD has been around for 30 years, so there’s a lot of stuff around that’s gone into it. But some things have to be designed in a bespoke [way], because a 24-hour race is equivalent to five grands prix in a row. The mission was to make the best racing engine across our racing future.”
When asked to explain further the methodology of the design and manufacturing process for the Acura ARX-06’s engine, Salters added: “We started with a clean sheet of paper, asking what we needed to make the best base racing car, then we looked around to see what we had racing engine-wise and what we needed to make.
“It turned out to be a combination of both. After that simulation we quickly made some single-cylinder parts, and proved the concept. Then we made a 2.4-litre V6, twin-turbo racing engine.”
