Many of the cars that ran "Merlins" didn't. The Merlin was supercharged & pretty complicated. What people like John Dodd ran, were Rolls Royce METEORS, the tank version of the Merlin, & still an impressive 27 litres but running on carbs. How do I know? I bought one, ex-military & still in the box, for £960, about 20 years ago. To impress people I told them it was a Merlin. Here's a pic of mine, originally destined for a Chieften tank. I never did get round to doing anything with it.