Porsche 963 Gets Weight Increase for Indianapolis

Photo: Brandon Badraoui/IMSA

The IMSA GTP championship-leading Porsche 963 has been handed a weight increase for this weekend’s Battle on the Bricks at Indianapolis Motor Speedway, following largely wholesale changes to the Balance of Performance for the Michelin Endurance Cup round.

Released on Monday by IMSA, the pair of factory Porsche Penske Motorsport entries, as well as JDC-Miller’s privateer 963, will face a 9kg increase in minimum weight since the most recent GTP round at Road America.

At 1060kg, the Porsche is now the heaviest GTP car by 18kg, and some 30kg heavier the baseline weight that the Acura now has, courtesy of an 8kg reductions for the ARX-06, as well as the Cadillac V-Series.R, the latter which is now at 1042kg.

The BMW M Hybrid V8 gets a minor 3kg increase, bringing it to 1036kg.

No weight changes have been made to either the Aston Martin Valkyrie or the returning Lamborghini SC63, which both remain at 1030kg, the same weight as the Acura.

In terms of power levels, Acura (-2.9 percent), BMW (-2.1 percent) and Cadillac (-2.3 percent) all receive notable reductions at first-stage power levels, while Porsche has a slighter decrease (-0.4 percent).

While the Cadillac retails its 99.6 percent maximum power at speeds over 240 km/h, Acura (-0.5 percent), BMW (-0.6 percent) and Porsche (-0.4 percent) all face slight reductions, with no changes to either the Aston or Lamborghini on power levels at either stage.

Porsche Penske’s Matt Campbell and Mathieu Jaminet lead teammates Felipe Nasr and Nick Tandy by 75 points, with the BMW M Team RLL of Dries Vanthoor and Philipp Eng sitting third in the title race, 181 points behind the leading No. 6 entry with two races to go.

The battle for the GTP manufacturers’ championship, however, is significantly closer, with Porsche holding just a 45-point lead over Acura, with BMW third, 148 points behind.

In the GT ranks, all cars except the Lexus RC F GT3 and Ford Mustang GT3 will have power reductions at the first stage.

The Lexus gains 0.8 percent of maximum power at speeds below 190 km/h, while the Mustang GT3 is unchanged since the last round at Virginia International Raceway.

The Chevrolet Corvette Z06 GT3.R has been hit the heaviest in the weight department, getting 10kg of additional ballast, while the BMW M4 GT3 EVO has a 1kg increase.

Ferrari’s 296 GT3, which is in a tight battle with Corvette in the GTD Pro championship, gets a 6kg weight break, while the Lamborghini Huracan GT3 EVO2 will be 2kg lighter.

While most first-stage power reductions are in the 1-2 percent range, the Corvette gets a 2.5 percent reduction, compared to the Ferrari at 3.9 percent.

Similar reductions are confirmed for the second-stage, at speeds over 200 km/h, which sees the Corvette face a 3.2 percent reduction and the Ferrari get 2.9 percent less power.

Of note, the Mercedes-AMG GT3 Evo has the biggest power reduction in second-stage, at -4.2 percent, while the minimum rear wing angle on the Porsche 911 GT3 R has been reduced from 10 to 8 degrees, although it will now have a maximum of 10.3 degrees.

The BMW has also had its minimum rear wing angle reduced, from 3 to 1 degrees, with a new maximum of 3 degrees.

John Dagys

John Dagys is the founder and Editor-in-Chief of Sportscar365. Dagys spent eight years as a motorsports correspondent for FOXSports.com and SPEED Channel and has contributed to numerous other motorsports publications worldwide. Contact John