Source: Vintage V12s

Rolls-Royce Griffon

The Griffon was designed prior to World War II and was originally intended as a low-altitude engine for naval aircraft such as the Fairey Firefly but a formal suggestion to fit a Griffon in a Spitfire was made by Joe Smith, who had taken over as Chief Designer at Supermarine's after Mitchell's death, in October 1939. However, work by Rolls-Royce on the engine had been halted temporarily to concentrate on the smaller 1,640 in³ (27L) Merlin which had already surpassed the output achieved with the early Griffon.

Engine Components
Valvetrain: Two intake and two exhaust valves per cylinder with sodium-cooled exhaust valve stems, actuated via an overhead camshaft.

Supercharger: Two-speed two-stage centrifugal type supercharger, boost pressure automatically linked to the throttle, water-air aftercooler installed between the second stage and the engine.

Fuel system: Triple-choke updraft carburetor with automatic mixture control

Oil system: Dry sump with one pressure pump and two scavenge pumps.

Cooling system: 70% water and 30% ethylene glycol coolant mixture, pressurized

Source: Wikipedia.com