Cadillac LMC55R engine

The Cadillac LMC55R engine is a naturally aspirated, four-stroke, 5.5-liter, V8 racing engine, made by GM Racing and Performance Center team for use in their Cadillac V-Series.R LMDh race car, since 2023.^[1][2]

Cadillac LMC55R engine
Overview
Manufacturer	Cadillac
Production	2023-present
Layout
Configuration	90° V8
Displacement	5.5 litres (336 cubic inches)
Cylinder block material	Aluminium alloy
Cylinder head material	Aluminium alloy
Valvetrain	32-valve (four-valves per cylinder), DOHC
RPM range
Max. engine speed	8,800
Combustion
Fuel system	Gasoline direct injection
Management	Bosch Motronic MS7 ECU
Fuel type	TotalEnergies (WEC) VP Racing Fuels (IMSA)
Oil system	Dry sump
Output
Power output	670 hp (500 kW; 679 PS)
Dimensions
Length	25.2 in (640 mm)
Dry weight	396.8 lb (180 kg)

Design

Cadillac developed the bespoke cross-plane engine for their 2023 Cadillac V-Series.R and is the only naturally aspirated engine of the LMDh manufacturers.^[3][4] In accordance with the LMDh rules, the LMC55R internal combustion engine is connected to the standardized hybrid drivetrain components provided by Bosch (motor generator unit), Williams Advanced Engineering (battery pack), and an Xtrac P1359 gearbox.^[5][6]

Applications

• Cadillac V-Series.R