Key to Porsche’s six-stroke engine is an eccentric crankshaft mechanism that changes the piston’s stroke, giving each cylinder two top and two bottom dead centers and three stroke lengths.

Key to Porsche’s six-stroke engine is an eccentric crankshaft mechanism that changes the piston’s stroke, giving each cylinder two top and two bottom dead centers and three stroke lengths ...

IndyCar engines must weigh at least 248 pounds, and the car at least 1,570. ... Pistons: The pistons are handmade to exacting, highly confidential specifications.