ignatz

Have been having a vibration problem with my GMPP LS376/515 crate engine that has a balanced (so I'm told) Centerforce Light Metal (LMC) flywheel and clutch assembly installed. To keep this query short and sweet, in the enclosed photo



there is a drill out of a few grams in the flexplate that was delivered with the motor. Is this there to fine tune the motor or to only balance the flexplate? Or neither.