IMSA Adjusts Balance of Performance for GTD PRO and GTD Categories Ahead of Michelin GT Challenge
The IMSA Technical Committee has announced significant changes to the Balance of Performance (BoP) for vehicles competing in the GTD PRO and GTD categories, effective at the upcoming Michelin GT Challenge at Virginia International Raceway. This sweep in regulations aims to enhance performance parity among GT3 entries across various circuits.
In a detailed statement, IMSA emphasized that their BoP process considers variations in vehicle aerodynamics, bodywork, and engine placements, which can lead to performance disparities. Utilizing tools such as torque sensors, wind tunnel data, and simulations, the Committee performs structured calculations to adjust for demonstrated performance trends.
Key adjustments include:
- Increased Maximum Stint Energy: All GT cars will see significantly raised maximum stint energy compared to Road America.
- Weight Adjustments: The BMW M4 GT3 EVO and Chevrolet Corvette Z06 GT3.R are subject to minimum weight increases.
- Horsepower Changes: Most models benefit from an initial horsepower increase under 190 kph, with notable exceptions for the Lamborghini Huracan GT3 EVO2 and Mercedes-AMG GT3 EVO, which will experience power reductions.
- Second Stage Adjustments: At speeds above 200 kph, power output has been decreased slightly for the Corvette and Porsche 911 GT3 R while significantly increasing for other models.
This marks the first season where magneto-elastic torque sensors are mandatory in GT3 vehicles, enabling real-time monitoring of powertrain compliance, with penalties imposed for violations.
Earlier this year, the BoP in the GTP category was manually adjusted, favoring the Acura ARX-06 and Cadillac V-Series.R while moderating the performance advantages of the Porsche 963 and BMW M Hybrid V8.
IMSA maintains ongoing engagement with manufacturer partners through regular discussions to refine the BoP processes, ensuring transparency and integration of feedback to better serve competitive integrity within the series.
