IMSA has set the Balance of Performance for all four classes ahead of next month's Roar Before the Rolex 24 at Daytona International Speedway.
The Prototype class sees minimal changes compared to the BoP utilized in last year's Rolex 24, with all cars remaining at the same base weight — and for the most part — the same air restrictor size.
Honda-powered P2 cars, however, will have a 7.5 mm larger air restrictor (32.5 to 40.0, x2), in addition to the displacement of its V6 twin-turbo increasing from 2.8 to 3.5 liters for 2016.
Fuel capacities have changed for a handful of cars, with the Corvette DPs seeing a 6 liter reduction, compared to a 5-liter cut for the Ford EcoBoost-powered Rileys and 2.3-liter reduction for the Hondas.
The Nissan-powered BR Engineering BR01, which will make its North American debut, has yet to receive minimum weight, fuel capacity and refueling restrictor numbers.
Fuel capacity and refueling restrictor for the new gasoline-powered Mazda engine have also yet to be finalized.
Prototype Challenge cars, meanwhile, will see a 10kg increase in minimum weight, compared to Daytona last year. No other changes are specified.
IMSA has also established the starting BoP for the GT Le Mans and GT Daytona classes, which predominantly feature all-new machinery, and therefore do not offer a direct comparison from last year.
A number of specifications remain to-be-determined, including the rear wing angle, gurney and fuel capacity of the Ferrari 488 GT3, refueling restrictor size for all GTLM and GTD cars, as well as the minimum weight and engine restrictor size for both the Ferrari 458 GT3 and new Audi R8 LMS.
Changes are expected to be made following data collected at the Roar, which runs from Jan. 8-10, in advance of the WeatherTech Championship season-opener at the end of the month.
IMSA has historically utilized a Daytona-specific BoP, with season-long changes being first rolled out for the Twelve Hours of Sebring in March.