BMW’s LMDh racer pairs a DTM V-8 with turbos and a hybrid system

BMW in June provided a first look at its new M Hybrid V8 LMDh (Le Mans Daytona hybrid) race car set to compete from next year in the new GTP (Grand Touring Prototype) class of the IMSA SportsCar Championship. GTP replaces IMSA’s current DPi (Daytona Prototype International) class as the new top class, and is open to both LMDh cars as well as LMH (Le Mans Hypercar) cars.

BMW has now followed up with the first details on the V-8 engine that forms part of the hybrid powertrain that will power its race car. The powertrain consists of a twin-turbocharged 4.0-liter V-8 and an electric motor, and in line with LMDh regulations the two power sources at any one time can generate a maximum output of 670 hp.

The V-8, code-named P66/3, is based on the 4.0-liter V-8 used in BMW’s former DTM racing program, specifically in the M4 DTM race car that competed in the 2017 and 2018 seasons. Time and cost restraints ruled out a new engine being developed from scratch, and the DTM engine was finally settled on because it was deemed as the best fit for the requirements of the LMDh regulations. BMW also looked at a 4-cylinder engine used in DTM and a twin-turbocharged 4.4-liter V-8 used in a GTE program, though these were ruled out due to durability and weight issues, respectively.

The P66/3 V-8 maintains the 4.0-liter displacement of the original DTM engine, but features more modern designs for the cylinder block and heads, as well as the turbochargers, and a new injection system which needed to be designed for direct injection. The engine banks are 90 degrees, and there are four valves per cylinder, plus dry-sump lubrication. The engine’s max speed is 8,200 rpm, and its regulated max output is approximately 640 hp and 479 lb-ft of torque.

2023 BMW M Hybrid V8 LMDh race car

2023 BMW M Hybrid V8 LMDh race car

2023 BMW M Hybrid V8 LMDh race car

2023 BMW M Hybrid V8 LMDh race car

2023 BMW M Hybrid V8 LMDh race car

2023 BMW M Hybrid V8 LMDh race car

As for the electric motor forming the hybrid system, it was developed using lessons learned from BMW’s Formula E program. The hybrid system consists of the electric motor, an inverter and high-voltage battery. The electric motor is mated with the V-8, with a separator clutch enabling the car to drive on electric power alone, which could be used in the pit lane, for example.

The complete hybrid powertrain was installed in the car and fired up for the first time at the end of June. An initial shakedown test is scheduled for the end of July, at a circuit in Varano de Melegari, Italy, and an intensive test program will proceed after that.

The first race will be the 2023 24 Hours of Daytona next January. The race is the opening round of the 2023 IMSA SportsCar Championship. BMW doesn’t plan to compete in the World Endurance Championship, but is expected to compete in the series’ highlight, the 24 Hours of Le Mans.

Acura, Alpine, Audi (maybe), Cadillac and Porsche are also committed to LMDh, while ByKolles, Ferrari, Glickenhaus, Peugeot, and Toyota are all committed to LMH. Lamborghini also announced in May that it will join the LMDh fold in 2024.

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