Rolls-Royce Merlin exhaust flow and waste-gates, meant that this option was rejected in favour of the two-stage supercharger. Fitted with the two-stage two-speed supercharger, the Merlin 60 series gained 300 horsepower (224 kW) at over the Merlin 45 series, at which altitude a Spitfire IX was nearly faster than a Spitfire V. The two-stage Merlin family was extended in 1943 with the Merlin 66 which had its supercharger geared for increased power ratings at low altitudes, and the Merlin 70 series that were designed to deliver increased power at high altitudes. While the design of the two-stage supercharger forged ahead, Rolls-Royce also
Rolls-Royce–Bentley L-series V8 engine any pre-2003 Rolls-Royce or Bentley engines. The current Rolls-Royce Phantom and its derivatives use a normally aspirated BMW V12 engine, which has no technical similarities with the L410 engine. The Rolls-Royce Ghost introduced in 2010 uses a 6.6-litre twin-turbo V12. Under Volkswagen Group, the Bentley Arnage's BMW engine was phased out from 2000 to 2002 and the L410 engine was reintroduced in highly redeveloped form. The Arnage-derived Brooklands uses the most powerful version of the engine yet. Those models and the convertible Bentley Azure are produced alongside the Bentley Mulsanne and smaller Bentleys based on the Continental GT, which use