After discussions with manufacturers, IMSA has confirmed the Balance of Performance going into the Rolex 24 at Daytona in the GT Le Mans and GT Daytona classes.
There are a handful of changes from the draft version, which was released earlier this week.
In GTLM, the Aston Martin Vantage GTE was to have had a 25 kg increase, but will not add that weight after all. It will remain at 1175 kg.
Additionally, the Aston was due to have a 0.6 mm air restrictor increase, but that has also been eliminated and the car will run at the same restrictor number.
A proposed 0.3 mm restrictor decrease for Porsche’s 911 RSR has also been removed.
Otherwise the 0.3 mm restrictor increases for BMW and Ferrari, and a 0.6 mm restrictor increase for Corvette, go ahead as planned from the draft version.
The biggest change in GTD comes to the BMW Z4 GT3, which is listed to receive a substantial restrictor increase of 19.0 mm to 84.0 mm.
The BMW and Porsche 911 GT America run with a single restrictor, while the Aston Martin, Audi, Dodge and Ferrari run with two.
Testing begins for the TUDOR United SportsCar Championship season opener with the Roar Before the Rolex 24 in two weeks, January 9-11, 2015.