BMW has been slowed, while Ferrari and Porsche have been given performance breaks in GT Le Mans ahead of next weekend’s Northeast Grand Prix at Lime Rock Park.

IMSA announced on Friday further Balance of Performance adjustments to the class, following a last-minute change issued just days prior to last weekend’s round at Canadian Tire Motorsport Park.

The latest round of BoP changes sees the Porsche 911 RSR gain 20kg of minimum weight, but now set to run with last year’s WEC-spec medium tire compound, which is expected to come as a gain.

The Porsche North America entries have recently struggled with Michelin’s new 2016 WEC-spec tire, which debuted at Mazda Raceway Laguna Seca.

Both the Ferrari 488 GTE and BMW M6 GTLM, meanwhile, have been given turbo boost adjustments, with the BMW facing a reduction in power and the Ferrari getting a slight increase.

Fuel capacities have also been adjusted for the Ferrari (+2 liters) and BMW (-2 liters), with the Prancing Horse getting a 1.0mm larger refueling restrictor as a result.

The Ford GT, which has claimed class victories in the last three races, has only received a 0.1 mm reduction in refueling restrictor, and no performance adjustments.

No changes have been made to the Corvette C7.R, which returned to form following the last round of adjustments prior to the Canadian round.

GTLM cars are set for its Lime Rock debut in IMSA WeatherTech SportsCar Championship competition, with the factory GT class having last visited the 1.5-mile Connecticut bullring in 2013 in ALMS.