Porsche and Aston Martin have received Balance of Performance changes ahead of next weekend’s FIA WEC Six Hours of Spa-Francorchamps.

The FIA Endurance Committee approved Thursday minimum weight adjustments for the two GTE cars, which will see the Porsche 911 RSR gain 25 kg and the Aston Martin Vantage V8 lose 15 kgs over the specification run at Silverstone.

The adjustments are applicable for both the GTE-Pro and GTE-Am classes, although no changes have been made Porsche’s 997-based 911 RSRs or the 2012 model Vantage, which is legal for GTE-Am competition.

Aston Martin Racing’s GTE-Pro entries struggled at Silverstone following an off-season ride height change that affected the balance of the V8-powered cars.

Porsche’s 911 RSRs, meanwhile, dominated the season-opening weekend in both dry and wet conditions.

The German manufacturer heads into next weekend’s second round of the season with a 20-point lead over Ferrari in the GTE Manufacturers’ Championship.