{{Use mdy dates|date=April 2025}} {{Infobox engine | name = Cadillac LMC55R engine | manufacturer = Cadillac | production = 2023-present | configuration = 90° V8 | displacement = {{convert|5463|cc|L|1|order=flip|abbr=on}} | bore = {{convert|104.25|mm|in|abbr=on}} | stroke = {{convert|80|mm|in|abbr=on}} | block = Aluminium alloy | head = Aluminium alloy | valvetrain = 32-valve (four-valves per cylinder), DOHC | redline = 8,800 | fuelsystem = Gasoline direct injection | management = Bosch Motronic MS7 ECU | fueltype = TotalEnergies (WEC)<br>VP Racing Fuels (IMSA) | oilsystem = Dry sump | power = {{convert|670|hp|kW PS|0|lk=on|abbr=on}} | length = {{convert|25.2|in|mm|0|lk=on|abbr=on}} | weight = {{convert|396.8|lb|kg|0|lk=on|abbr=on}} }}
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.<ref>{{Cite web |last=Perkins |first=Chris |date=2023-07-28 |title=Cadillac's Big Naturally Aspirated Race V-8 Is a Monster In a World of Small Turbo Engines |url=https://www.roadandtrack.com/car-culture/a44665266/cadillac-lmdh-v-8-analysis/ |access-date=2025-04-18 |website=Road & Track |language=en-US}}</ref><ref>{{Cite web |title=V-SERIES.R RACE CAR |url=https://www.cadillac.com/performance/racing#racecar |archive-url=https://web.archive.org/web/20250409013922/https://www.cadillac.com/performance/racing#racecar |archive-date=2025-04-09 |access-date=2025-04-18 |website=www.cadillac.com}}</ref>
== Design == Cadillac developed the bespoke cross-plane engine for their 2023 Cadillac V-Series.R and is the first naturally aspirated engine of the LMDh manufacturers.<ref>{{Cite web |last=Lopez |first=Jonathan |date=2023-08-13 |title=Here's A Look At The Cadillac LMC55.R V8 Engine |url=https://gmauthority.com/blog/2023/08/heres-a-look-at-the-cadillac-lmc55-r-v8-engine/ |access-date=2025-04-18 |language=en-US}}</ref><ref>{{Cite web |title=Wayne Taylor Racing |url=https://waynetaylorracing.com/carspecs/ |archive-url=https://web.archive.org/web/20250116094535/https://waynetaylorracing.com/carspecs/ |archive-date=2025-01-16 |access-date=2025-04-18 |website=waynetaylorracing.com}}</ref> 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.<ref>{{Cite news |last=Newbold |first=James |date=December 18, 2022 |title=Inside the spec hybrid spine of LMDh cars |url=https://www.motorsport.com/imsa/news/inside-the-spec-hybrid-spine-of-lmdh-cars/10412551/ |archive-url=https://web.archive.org/web/20250114231314/https://www.motorsport.com/imsa/news/inside-the-spec-hybrid-spine-of-lmdh-cars/10412551/ |archive-date=January 14, 2025 |access-date=2025-04-18 |language=en |url-status=live }}</ref><ref>{{Cite web |last=Goodwin |first=Graham |date=2022-07-08 |title=Cadillac Shake Down New LMDh Racer |url=https://www.dailysportscar.com/2022/07/08/cadillac-shake-down-new-lmdh-racer.html |access-date=2025-04-18 |website=www.dailysportscar.com |language=en-GB}}</ref>
== Applications ==
== References == {{Reflist}} Category:Cadillac engines Category:Cadillac in motorsport Category:V8 engines Category:Gasoline engines by model Category:2020s automobile engines