Yes, but as I've said, for performance applications, you need to shoot for parallel under acceleration. How much pinion angle is a guess totally dependent upon "how much" the car pulls the pinion up on cruise acceleration for a street car, or hard launch for a drag car. There is no ONE answer for everything. Drive shafts will ALWAYS vibrate somewhere in the RPM range. The trick is to get the vibration OUT of the operating range of a given application.
