Rolls-Royce–Bentley L-series V8 engine as the "six and a quarter" litre engine. When new, the Rolls-Royce/Bentley V8 was rumoured to be an American engine design licence-built, but it was developed in-house by Rolls-Royce and Bentley engineers. This can be seen in its design characteristics, with features like an aluminium alloy cylinder block with wet liners, gear-driven camshaft, (initially) outboard spark plugs and porting inspired by the Rolls-Royce Merlin aircraft engine. The bore spacing of 4.75" was unlike any American V8 engine and the firing order was 1-5-4-8-6-3-7-2 something uncommon in any period American OHV V8. The deep skirted crankcase design is also rare with
Rolls-Royce Holdings 2007 that production of the Trent 900 had been restarted after a twelve-month suspension caused by delays to the A380. On the military side, Rolls-Royce, in co-operation with other European manufacturers, has been a major contractor for the RB199 which in several variants powers the Panavia Tornado, and also for the EJ200 engine for the Eurofighter Typhoon. Two modified RB199 engines also powered the EAP demonstrator which evolved into the Typhoon. Rolls-Royce has matured the Rolls-Royce LiftSystem invented by Lockheed Martin for the Joint Strike Fighter (JSF) F-35 Lightning II to production level, planned to be produced in significant numbers.