iRacing has just released its August development update ahead of Season 4 of 2025, which includes 3 new cars, a new current F1 race track, the final stage of their “NASCAR Refresh”, track rescans and art updates, the long-awaited new UI, eye-tracking foveated rendering for improved VR performance, and much more. Let’s take a closer look at the new content.
iRacing Season 4 2025 New Cars & Tracks
Those 3 new cars being added to iRacing for the final season of 2025 are the Aston Martin Vantage EVO GT3, the INDY NXT series Dallara IL-15 formula car, and the Ford Mustang GT4.
The addition of Aston Martin’s Vantage EVO means iRacers will now have 11 GT3 cars to choose from on the service, with the challenge for iRacing being to establish a good balance of performance (BOP) so that the higher GT3 and IMSA splits aren’t just full of one or two ‘OP’ cars.
The release of the Ford Mustang GT4 also coincides with a number of significant updates for the existing GT4 field, including updates to the TC, ABS, and ESC systems, brake systems, and aerodynamics. Expect to see higher top speeds on the straights, but with lower minimum corner speeds, equating to a decrease in overall GT4 lap times of between 0.5 and 1.0 seconds per lap on average.
Meanwhile, the Dallara IL-15 formula car, which races in real life INDY NXT series, is powered by 2.0-liter turbocharged 450hp power unit and will be a Class C license on iRacing in both Road and Oval Fixed.
There’s also good news for owners of the BMW M4 GT3, with iRacing set to update the car to its current EVO model at no extra cost.
iRacing’s development update also gave us confirmation of Autódromo Hermanos Rodríguez, Mexico City becoming the new track being added for next season. F1 fans will know this circuit best as the home of the Mexican F1 Grand Prix, but it also hosts TCR, NASCAR, and Formula E motorsport events, to name just a few.
There’ll also be an art update for one of iRacing’s most popular base content tracks, Oulton Park, where developers have been updating the British track’s artwork by remodelling and retexturing all the objects and scenery. Although this isn’t an actual rescan, the track surfaces have been updated, along with the trees and foliage.
Is iRacing adding the Mustang Dark Horse?
Although it’s now been confirmed that the Mustang GT4 is coming, many people would have actually preferred to have seen the Mustang Dark Horse R car, which currently competes IRL in the IMSA-sanctioned Ford Mustang Challenge series.
The current Mustang on iRacing, the FR500S, was added not long after the sim’s launch 17 years ago and is still yet to be replaced by the Dark Horse. And with the FR500S no longer part of the Production Car Challenge multi-class series, the only series you can race it in on iRacing now is their version of the Mustang Challenge.
Despite the FR500S still being one of the most fun cars to drive on iRacing, once you get the hang of it, the fact that it’s been on the service so long and is still full-price paid content has contributed to low participation numbers in official series. Many iRacers are now simply waiting for the Dark Horse before getting back into the series.
Rumours suggest that iRacing does indeed intend on adding the Mustang Dark Horse R to the service, but it won’t be ready for at least a couple more seasons. So potentially sometime in mid-to-late 2026, but there’s no official confirmation of this.
All new content that has been announced should become available early on during Week 13 of the current season, ahead of a new season of official races in S4 2025.