The electric powertrain that debuted in the Porsche Mission R Concept last year at the IAA Mobility in Munich lives on in the new 718 Cayman GT4 ePerformance test vehicle.
Like the Mission R, the all-wheel-drive racer uses the chassis of the proven 718 Cayman GT4 Clubsport model, while the entire electric motor and battery technology comes from the Mission R study.
The powertrain has a maximum output of 735 kW (986 horsepower) in qualification mode or 450 kW (603 horsepower) in simulated racing for 30 minutes—the duration of a Carrera Cup race. For short bursts, the peak output reaches 800 kW (1,073 horsepower).
Porsche says that's enough to give the 718 Cayman GT4 ePerformance similar lap times and top speed to the current 992-generation 911 GT3 Cup race car.
The fully electric drivetrain is based on a permanently excited synchronous machine (PESM) on the front and rear axles, which make the race car prototype an all-wheel-drive machine. The electric motors and battery pack feature direct oil cooling developed by Porsche to counteract thermally induced derating, enabling the car to sustain a constant power output during 30 minutes of racing.
Gallery: Porsche 718 Cayman GT4 ePerformance
"The integration of oil cooling has significantly impacted the vehicle concept. With experts in the fields of aerodynamics and thermodynamics as well as high-voltage and bodywork specialists, the development team created an architecture to tap the full potential of the battery cells for the first time, since there is no thermal derating. In this way, the power output in racing mode remains constant for half an hour."
Björn Förster, GT4 ePerformance project manager
Furthermore, the vehicle runs on a 900-volt electrical architecture which enables the state of charge of the battery to jump from 5 to 80% in about 15 minutes at full charging capacity.
The body shell of the 718 Cayman GT4 ePerformance is 5.5 inches (140 mm) wider than the 718 Cayman GT4 Clubsport to accommodate the wider 18-inch Michelin racing tires. The bodywork features about 6,000 parts designed from scratch and is made of natural fiber composite materials, while recycled carbon fibers are also used for testing purposes.
Porsche will debut the 718 Cayman GT4 ePerformance at the Goodwood Festival of Speed (June 23–26), where the electric racer will take place in the hill-climb event. The car will make a second public appearance on August 20 at the Porsche factory in Leipzig for the site's 20th anniversary.
Porsche has built two 718 Cayman GT4 ePerformance demo vehicles, which will embark on a world tour this year starting with various European countries before heading to North America in early 2023. The tour will conclude in the Asia-Pacific region in mid-2024.