Balance of Performance (BoP)
The “Balance of Performance” applies to the GTLM class of the IMSA SportsCar Championship. “BoP” was introduced by the IMSA with the aim of achieving a level playing field for the different vehicle concepts in this famously competitive class, and thus ensure balanced and fair races. It should not make a fundamental difference if a vehicle is powered by a turbocharged or normally aspirated engine, or if the engine is mounted on the front axle or in front of the rear axle. The basic aerodynamic shape of the vehicles should also not play a decisive role.
After an initial grading by the IMSA, the performance data of the vehicles are acquired during the races via telemetry – not only lap times but, for example, acceleration profiles and engine mappings. This data input is then analysed and incorporated into the “BoP”. The most frequently used means of adjusting the performance level is through adding or subtracting weight as well as increasing or limiting the engine output through a restrictor or boost. In keeping with the rule-makers’ intention, the key to success on the racetrack is not about the individual potential of a vehicle, instead it’s about the performance of the drivers, the race strategy, a perfect setup or the skill of the team with their pit stops.