IMSA has made a third Balance of Performance adjustment to the Chevrolet Corvette C8.R GTD in four events this season following a further weight increase to the car ahead of next weekend’s Hyundai Monterey Sports Car Championships at WeatherTech Raceway Laguna Seca.
In a BoP change issued on Thursday afternoon, the Corvette will run 20 kg heavier than it did at the most recent WeatherTech SportsCar Championship round at Long Beach.
The 1370 kg minimum weight is now on par with the Mercedes-AMG GT3 Evo as the heaviest GT3/GTD-spec car in the category.
While having run a 15 mm tall gurney in the opening three rounds, IMSA has cut that to 10 mm, which is expected to affect straight-line speed and potentially cornering ability on the twisty 2.238-mile circuit.
Other BoP changes for Laguna Seca include a power reduction in the range of 6 horsepower for the BMW M4 GT3 and a 10 kg increase in minimum weight for the Cadillac DPi-V.R.
The Acura ARX-05, meanwhile, has retained its 10 kg weight break given prior to Long Beach, meaning there is now a 35 kg weight difference between the Acura (920 kg) and the Cadillac (955 kg) in the DPi class.