General Motors may be in the middle of transitioning to all-electric powertrains, but that doesn’t mean The General is done with internal combustion. Quite the contrary – in fact, GM’s ICE-based efforts extend all the way to France and the 24 Hours of Le Mans, where Cadillac managed to podium with the impressive LMC55.R cross-plane V8 engine. Now, we’re getting a closer look at the Cadillac LMC55.R V8 thanks to the following photos.
Recently making the rounds on social media, the photos present the Cadillac LMC55.R V8 both inside and outside the car, showing off the structure of the powerplant and a few of the technical details.
The LMC55.R V8 was designed and built by the team at the GM Racing and Performance Center in Pontiac, Michigan, and is the only hybrid naturally aspirated engine competing in both the WEC Hypercar class and IMSA GTP class. Contributions were also made by Roush Advanced Composites.
Making its debut in June of 2022, Cadillac’s LMC55.R V8 features 5.5 liters of displacement, dual overhead cams, 32 valves, and a 90-degree cylinder configuration. The engine also features “advanced materials and manufacturing techniques” (per Cadillac) that enable it to be mounted as a structural component in the Cadillac V-Series.R racing machine (also known as the Cadillac V-LMDh).
The LMC55.R V8 is also the only naturally aspirated engine in the IMSA GTP class. Peak power output is rated at 670 horsepower, while peak torque output is specific to the series in which the race car is competing.
Further details include dry sump lubrication, while output is routed through the Xtrac P1359 seven-speed sequential gearbox. The V8 is paired with a rear-mounted 50 kW electric motor. The Cadillac V-Series.R chassis is an LMP2-based cabon fiber monocoque, while vehicle weight tips the scales at 2,380 pounds.
Per a recent social post from Vince Tiaga, a team member at the GM Motorsports Competition Group, the decision was made to go with a naturally aspirated, cross-plane V8 as not only did it meet the team’s requirements, but it also “promised to deliver a distinctive sound that would make it easily identifiable as it roared around the track.”