The Pontiac cammer 6 was made in 230 and 250 cu in sizes. The "sprint" version made 215 HP with a 4 barrel and dual exhausts. Car & Driver magazine put one in a Jag. Purists were not amused.
They can be found in wrecking yards but the cams and cam journals are a weak point and no replacement parts are available. Too bad;it was a good motor.
