IMSA Makes Significant BoP Changes for Rolex 24

Photo: John Dagys

IMSA has released the expected final Balance of Performance prior to next weekend’s WeatherTech SportsCar Championship season-opening Rolex 24 at Daytona, with significant changes having been made in all four categories.

Here’s a rundown of the changes since the initial 2016 BoP, which was utilized at the Roar Before the Rolex 24 earlier this month.

Prototype:

*BR Engineering BR01 Nissan: 10kg weight reduction (890 to 880kg), confirmed fuel (76 liters) and refueling restrictor (33.0mm)

*DeltaWing DWC13 Coupe: 5kg weight increase (515 to 520kg), 0.19 reduction in boost ratio

*Ligier JS P2 Honda: 10kg weight increase (940 to 950kg), slight reduction in boost ratio at selected RPM levels

*Ford Riley DP: Slight reduction in top-end RPM boost ratio

*Lola B11/80 Mazda: Reduction (0.026-0.126) in boost ratio, 8-liter increase in fuel capacity and defined 33.0 mm refueling restrictor

*Dinan Riley DP: 2mm larger restrictor (74 to 76mm x 2)and 2-liter increase in fuel capacity (79 to 81 liters)

*Corvette DP: No changes

Prototype Challenge:

*Revised rear wing position (P6 to P4), new minimum angle of -9.8 degrees and -19.8 degrees for the flap. IMSA will issue a specific bulletin describing the rear wing measurement

GT Le Mans:

*BMW M6 GTLM: Reduction in boost ratios, larger Gurney (5 to 15mm), 9-liter increaase in fuel capacity (95 to 104 liters), 33.5mm refueling restrictor

*Corvette C7.R: 0.2 mm smaller air restrictor (30.1 to 29.9mm x2), 6-liter increase in fuel capacity (86 to 92 liters), 32mm refueling restrictor

*Ferrari 488 GTE: Slight reduction in boost ratios, confirmed 78 liters fuel capacity and 29.5mm refueling restrictor

*Ford GT: Reduction in boost ratios, 3-liter increase in fuel capacity (95 to 98 liters), 35mm refueling restrictor

*Porsche 911 RSR: 6 liter increase in fuel capacity (85 to 91 liters), 32mm refueling restrictor

GT Daytona:

*Aston Martin V12 Vantage GT3: 10kg weight reduction (1260 to 1250kg), 1.3mm larger air restrictor (40.7 to 42mm x2 ), 13-liter increase in fuel capacity (90 to 103 liters)

*Audi R8 LMS ultra: 10kg weight reduction (1300 to 1290kg), 1.7mm larger air restrictor (52.3 to 54mm x2), 3-liter increase in fuel capacity increase (104 to 107 liters)

*Audi R8 LMS (new): 20kg weight increase (1280 to 1300kg), 2mm reduction in air restrictor (40 to 38mm x2), 4-liter increase in fuel capacity (86 to 90 liters)

*BMW M6 GT3: 10kg weight increase (1300 to 1310kg), reduction in boost ratios, 9-liter increase in fuel capacity (95 to 104 liters)

*Dodge Viper GT3-R: 20kg weight reduction (1340 to 1320kg), 1mm reduction in air restrictor (39 to 38mm x2), 4-liter increase in fuel capacity (103 to 107 liters)

*Ferrari 458 Italia GT3: 20kg weight reduction (1300 to 1280kg), 200 rpm reduction (8400 to 8200 rpm)

*Lamborghini Huracan GT3: 20kg weight increase (1260 to 1280kg), 2mm smaller air restrictor (39 to 37mm x2), 1 liter increase in fuel capacity (89 to 90 liters)

*Porsche 911 GT3 R: 1 liter reduction in fuel capacity (85 to 84 liters)

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