You know I never realy thought about that.I would think the deciding factor would be intake maniflod.I know the mild porting was good for about 15 HP but that is from a fairly free flowing head to start with
71 duster,looking for input on crank pulley alighnment to water pump with font motor plate.Was wondering if anybody has machined down water pump housing on the back the thickness of the motor plate or if i have to shim out crank pulley.THANKS.