iRacing’s 2025 Season 4 update includes three new cars, the Mexico City circuit, a rework of the hybrid system, a new user interface and multiple minor updates to existing cars and tracks. Let’s dive into the details.
Dallara IL-15
Another new car will slot into the intermediate open-wheel series in iRacing. Although the Dallara IL-15 was designed more than 10 years ago for the Indy NXT (ex Indy Lights) championship, it aged surprisingly well.
The IL-15 produces 450 horsepower, with an additional 50 horsepower available through P2P. The car is very light, weighing in at 626 kg, and generates a considerable amount of downforce through its wings and underbody tunnels.
It should be a popular alternative to Super Formula Lights for drivers who prefer circuits in North America and IndyCar design.
Ford Mustang GT4
iRacing is continuing to expand its GT4 series. Leading this effort is the introduction of the Ford Mustang GT4 – the first North American brand to join the class.
A naturally aspirated 5.0-litre V8 engine powers the car. Restrictors limit the output to somewhere between the mid-400s and mid-500s horsepower, depending on the circuit. Despite weighing around 1,450 kg, it can reach 250 kph and stop impressively late into corners thanks to its brakes and aero.
Aston Martin Vantage EVO GT3
The ever-growing lineup of GT3s in iRacing will receive another car in Season 4 – Aston Martin Vantage EVO GT3.
The Aston Martin Vantage has been a key contender in GT3 racing since the debut of the V12 Vantage GT3 in 2012. The current-generation Vantage GT3 was introduced ahead of the 2019 motorsport season and upgraded to the EVO version in 2024. It features a 4.0-litre twin-turbo V8 engine, producing approximately 535 horsepower.
Other Car Updates
The entire GT4 field has received a physics refresh designed to better align with IMSA Michelin Pilot Challenge regulations. Baseline weight and engine power have been increased, while both dry and wet tyres have been rebuilt using a new tyre model. Grip levels are slightly lower, which means higher top speeds but reduced cornering speeds. Lap times are expected to improve by up to a second, depending on conditions.
Hybrid systems have undergone a fundamental overhaul, integrated into a new power unit framework capable of supporting the diverse range of hybrid technologies in the sim. LMDh and LMH classes now blend internal combustion and electric drive, so the Ferrari 499P can deploy electric power at multiple levels once above a minimum speed.
GT3 class receives tweaks to gear-ratio options as a part of the BoP process. Owners of the BMW M4 GT3 can also enjoy a free Evo upgrade to the BMW M4 GT3. This required substantial graphics and physics work, and the update will be applied on top of the existing BMW M4 GT3. Therefore, the update will be free for all iRacers who own the BMW M4 GT3.
iRacing –
- Fastest LMGT3, LMP2, Hypercar & GTE Setups
- AI Coaching for Sector by Sector Improvement
- Challenge Racers on the Delta Leaderboards
- The Best Telemetry App to Get Faster Today
Autodromo Hermanos Rodriguez
Mexico City makes its iRacing debut in Season 4. The track is known for hosting events from Formula 1 and NASCAR to numerous Touring and GT series.
It is presented in seven different configurations to suit a wide range of cars and competitions. The main Grand Prix layout is 4.3 km long and features a 1.2 km front straight. The track is situated 2,238 metres above sea level, which enables cars to reach remarkable top speeds on the main straight because of low drag.
Other Track Updates
iRacing continues to refresh and rescan existing circuits. The following updates are scheduled for Season 4:
Refreshes
- Oulton Park
- Daytona International Speedway
- Circuit of the Americas
- Watkins Glen International
- Chicago Street Course
- Texas Motor Speedway
Rescans
- World Wide Technology Raceway
- Charlotte Motor Speedway
- North Wilkesboro Speedway
- Sonoma Raceway
- Rockingham Speedway
Updates will be free for current owners of these tracks.
New iRacing UI
The legacy iRacing Sim UI has served well for many years, but its outdated and rigid architecture has limited further development. Around two years ago, iRacing began developing a modern replacement designed to handle complex performance demands and multiple display types.
The first version of the new UI is now complete and will launch with all the features of the legacy system, alongside improved design, expanded functionality and a more modern presentation.
Key improvements include tooltips for most controls, a redesigned Options menu with clearer organisation, easier UI movement controls, new options for adjusting the virtual mirror, a redesigned Camera Tool accessible via a dedicated button and many other updates.
Coach Dave Academy’s Plan for the iRacing 2025 Season 4
Our professional drivers and engineers will continue to develop the best setups for popular series for Season 4 iRacing.
Next week, we will provide you with a detailed overview of all the classes, cars, and series we are covering, along with the data, lap guides and information we will be providing.
Yes, the brand new Aston Martin GT3 Evo and Ford Mustang GT4 will be included in our plans!
iRacing –
- Fastest LMGT3, LMP2, Hypercar & GTE Setups
- AI Coaching for Sector by Sector Improvement
- Challenge Racers on the Delta Leaderboards
- The Best Telemetry App to Get Faster Today
