Over the past several iRacing seasons, the Ford Mustang GT4 has continued to evolve through a series of Balance of Performance (BoP) and tire model adjustments. While the car has maintained its signature V8 character and predictable handling, iRacing’s refinements between 2021 and 2025 have made it more consistent and competitive across the GT4 field.
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➡️Everything about Ford Mustang GT4
Balance of Performance Improvements
Each iRacing quarterly build typically reviews GT4 class balance, and the Mustang has seen small but meaningful tweaks to its weight, power, and aero performance. These adjustments were aimed at keeping parity with other GT4 cars such as the Porsche 718 Cayman GT4 Clubsport MR, McLaren 570S GT4, and BMW M4 GT4. The Mustang often benefitted from improved stability and mid-corner rotation without losing its straight-line speed advantage.
Tire Model Refinements
Perhaps the most noticeable change to the Mustang GT4 came with updates to iRacing’s tire model. Drivers immediately reported smoother breakaway characteristics and more predictable grip through long stints. The updated tires deliver better heat management and less aggressive degradation, allowing the Mustang to remain competitive even in endurance events.
Under braking, the new tire model provides greater feedback, reducing flat-spot tendencies and helping drivers modulate pressure more precisely — particularly important for those running longer races or sharing the car in team events.
Improved Drivability
With these changes, the Mustang GT4 has become one of the most approachable cars in the GT4 lineup. It rewards smooth inputs and throttle control but is no longer as punishing over curbs or in transitions. Drivers who previously found the car “snappy” on corner entry now experience greater confidence and balance through fast-flowing corners.
These cumulative updates have kept the Ford Mustang GT4 firmly in the fight throughout iRacing’s GT4 series and special events. While other cars may excel on tighter technical circuits, the Mustang’s mix of torque, stability, and now refined tire behavior makes it a versatile and enjoyable option across nearly every track.
