It’s easy to associate the ‘60’s with big V8 engines and ridiculous horsepower, but there was a lot of innovation with small engines too. While America was building bigger and bigger V8’s, Formula One had lowered the maximum engine displacement to just 1.5 liters (just 91 cubic inches). These motors made between 150 and 225 horsepower, which actually ain’t too shabby for 60’s four-bangers. But America can do better.
Hemmings Auto Blog came across this odd-yet-awesome Mickey Thompson “Twin-Tempest” engine. With just two cylinders and a supercharger, this bite-sized piece of badassery made over 250 horsepower. Stick that in your pipe, F1.
Mickey Thompson is a man well-known for his various speed and endurance racing records. He is also forever immortalized on the tire brand that bears his name, but he was heavily involved in engines as well. In 1961, he wanted to take the F Class for land speed racing, which only allowed for engines between 61 and 91 cubic inches. While Thompson could have opted to use some small, foreign engine, he decided to get creative.
He used half of a Pontiac Tempest “Trophy” motor, itself already halved from the Pontiac 389 engine. Basically, he was working with a ¼ of a V8 engine, covering the open side of the new two-cylinder motor with aluminum plates. With a single Hilbourn injector and a GM 2-71 supercharger, the “Twin Tempest” as it was called could spin to 8,500 RPM and made 257 horsepower. It was dropped into a non-streamliner Dragmaster chassis and turned consistent 106 mph runs in the standing mile. Not bad for a two-cylinder engine, eh? Why can’t the Big Three be this creative?