Corvette Racing and Porsche have each received Balance of Performance adjustments ahead of round six of the FIA World Endurance Championship at Sebring next weekend.

The Chevrolet Corvette C8.R, which raced in the WEC for the first time at Circuit of The Americas last month, will gain power through a larger air restrictor granted by the automatic BoP system.

The diameter of the restrictor controlling how much air enters the car’s 5.5-liter naturally aspirated V8 engine has been increased from 41.3mm to 42.8mm.

Corvette struggled on its WEC debut at COTA, finishing three laps down and sixth out of seven cars in the GTE-Pro category despite having a trouble-free race.

The GM brand is returning to world championship action at Sebring, where it will continue its preparations for the C8.R’s first 24 Hours of Le Mans appearance in June.

Additionally, the two factory Porsche 911 RSR-19s have been handed 23 kg weight increases for the German manufacturer’s defense of its 1000 Miles of Sebring GTE-Pro crown.

This brings the Porsches up to a minimum weight of 1277 kg, putting them just three kilos shy of the heaviest in car class which is the Ferrari 488 GTE Evo.

At COTA, Porsche had the third-heaviest car behind Ferrari and Aston Martin, but it’s now the second-heaviest of the four manufacturers.

A slight 0.5 mm air restrictor increase has been applied to counteract the weight increase, while the Porsches’ fuel tank capacities have also been increased, by three liters.

AF Corse Ferrari Heaviest in GTE-Am

The championship-leading No. 83 AF Corse Ferrari will be the heaviest GTE-Am car at Sebring, according to the latest success ballast table which was also published on Tuesday.

The car shared by Nicklas Nielsen, Emmanuel Collard and Francois Perrodo will run at 1285 kg, owing to its 15 kg penalty for being on top of the points standings.

The two Aston Martin Vantage GTEs from TF Sport and Aston Martin Racing will be joint second-heaviest on 1272 kg, while three other Ferraris from Red River Sport, MR Racing and AF Corse are all at 1270 kg.

Porsche’s heaviest GTE-Am car is the No. 57 Team Project 1 machine at 1244 kg, while the German squad’s sister No. 56 car and the Gulf Racing entry are both 10 kilos lighter.

The lightest cars in the field are the two Dempsey-Proton Racing Porsches which will carry identical minimum weights of 1229 kg.