The undeniable speed advantage enjoyed by the turbocharged Ford and Ferrari GTE Pro cars in practice and qualifying has been met with significant Balance of Performance changes just over 24 hours before the start of the 24 Hours of Le Mans.

The pole-winning ford GTs, which qualified 1-2-4-5 in the 14-car class, have received an extra 10kg of ballast, moving the four cars up to 1,248kg, but that’s only a token change. The big pre-race adjustment is the removal of boost pressure throughout the twin-turbo V6’s rev range from 4,200-7,000rpm. Only the Ford’s peak 7,100rpm range was left untouched.

On the Ferrari side, its new twin-turbo V8 488 was met with the opposite treatment as its boost was left alone in favour of reducing its pace through bolting an extra 25kg to the three Prancing horses that qualified P3-6-7. The 488s also received and extra four litres of fuel capacity.

The slow non-turbos from Aston Martin, Corvette, and Porsche also had BoP changes made, and most were in the name of improving their pace.

Aston’s V8 Vantages will breathe easier thanks to a further 0.4mm opening of its air restrictors, which will increase power and torque. The Corvette C7.Rs received a 0.3mm air restrictor break, but the team only has restrictors in hand that would allow a 0.2mm break.

“It’s a move in the right direction,” Corvette Racing program manager Doug Fehan said. “The [0.3mm] is enough of an improvement that we need to find a solution because we only have restrictors that will get us [0.2mm].”

The C7.Rs were also given an additional seven litres of fuel capacity. The Porsche 911 RSRs did not receive weight or air restrictor changes, but now have eight litres of new fuel capacity.

“What we do as a race team is we race the race and try to minimise the things that can stop you from being at the front at the end,” Chip Ganassi Racing managing director Mike Hull said in light of the changes. “You win on racecraft, take what’s given to you, and the faster you accept that, the faster you can push yourself to find the best strategy.

“What I like about what’s happened is it’s a compliment to what’s Ford’s done and the team’s done and the sanctioning body’s done. They try to make it fair. You have to accept what you’re given. It’s the most carnivorous class of racing. The race will demonstrate who has the best racecraft.”

Altogether, the changes to the Ferraris and Fords should make for an intense fight among GTE-Pro cars throughout Saturday and Sunday in La Sarthe.