Acura, Cadillac, Porsche and BMW all had to adhere to the same minimum weight limit of 1030kg for January's Rolex 24 at Daytona, the first race for the new breed of hybrid-powered LMDh cars in IMSA.
But the sanctioning body has decided to increase the minimum weight by a varying degree for each of the four manufacturers, with the Daytona-winning Acura ARX-06 now required to run at or above 1054kg.
This marks a 24kg increase over the season opener and means the ARX-06 will be 16kg heavier than the rebranded Cadillac V-Series.R, which will now be the lightest car in the category at 1038kg.
The BMW M Hybrid V8 and the Porsche 963 must weigh 1040 kg and and 1048 kg respectively, without taking into account the driver or the fuel load.
The power figures for the Sebring International Raceway round have also been adjusted, although in this case it is Acura which has received the biggest jump among the GTP marques.
The Meyer Shank Racing and Wayne Taylor Racing-run Acuras will be allowed to race at a maximum power of 520 kW, a 20 kW bump from the Daytona round - where power units of all four manufacturers were capped to 500 kW.
The Porsche 963 entered by the factory Penske team will be the closest to the ARX-06 in this regard, with the German manufacturer allowed to run the car at 517 kW.
The Cadillac (fielded by Action Express Racing and Chip Ganassi Racing) and the BMW (entered by the works RLL outfit) have been allotted the same useable power at 513 kW.
The maximum energy allowed in a stint has correspondingly been increased to 917 kW for the Acura, 912 kW for the Porsche and 905 kW for both the Cadillac and BMW.
The 2022 edition of the Sebring 12 Hours was won by the #02 Cadillac of Earl Bamber, Alex Lynn and Neel Jani, with the General Motors brand locking out the podium spots between its CGR, AXR and JDC-Miller teams.
MSR goes to Sebring on the back of its second consecutive victory at Daytona, but was hit with a $50,000 fine and a loss of 200 championship points on Wednesday after being found guilty of manipulating tire pressure data.
