760 hp Gremlin

and David says that at the end of the Gremlin timeline, they offered a 4 cylinder engine for better economy, and to be cheaper than the 6 cylinders. That engine was the same 4 cylinder engine used in the Porsche 924, Audi 100, and VW van.   An Audi 100 2.0 liter four-cylinder engine

The Porsche of course had a slightly modified version, those featured a beefed-up, forged crankshaft and larger bearings in the cast-iron block case with a Porsche-designed aluminium cylinder head.

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