Flywheel drive: 4 pin or 8 pin?

Mike von S.

Well-Known Member
Supporting Member
Feb 4, 2021
I recently spent 1/2 day with a very experienced race VW engine builder. Years ago, his attorney advised him never to touch an aero conversion, for fear of liability. He was willing, however, to take a close look at my GPAS flywheel drive kit. He found much to criticize. If anyone cares, I can comment further. However, my immediate question concerns the flywheel/starter ring connection to the crank. My guy was astonished to see that GPAS only uses a 4 pin connection.
Can any of you comment on whether there is a reason for this?
I have ordered a 4 pin - 8 pin drilling jig from CB Performance, but thought I better ask this group if there might be a structural reason not to add the additional holes to the flywheel/starter ring?