محرك صاروخي
The later (1961-1963) 9:1 compression ratio Super Rocket engine was used with a 357 "Spitfire" camshaft and a 1 5/32" bore Amal Monobloc carburettor which gave as standard. Options such as an Amal GP2 carburettor, "siamesed" exhaust pipes and a close-ratio RRT2 gearbox could increase this to – and add 30% to the price. Nine specials were made for export to California and one was fitted with a sidecar by Watsonian for the Earls Court Show in October 1962.