1992 Miata, LS1, then LS3 swapped

[mazpower]

Originally Posted by GySgtFrank

I was crewing for a stock car running a chevy 250 straight 6 a number of years ago. Had the same problem. No matter what we did it would spit off flywheels, even the LocTite didn't help. It turned out it was some sort of weird harmonic that kept loosening the bolts. We put a Fluidampr front vibration dampener on it and it cured the problem.

Interesting...I'm running a SLP front dampener on this build cause its keyed, as is my crankshaft and I wanted solid timing marks (LSx engines don't have keyed pullies or cranks from the factory, no timing marks either). The engine is pretty damn smooth through the rev range. I've heard that spec clutch assemblies can be out of balance though, I wonder if that contributed to it? I've been running the same flywheel/clutch combo since the beginning and this is the first time I've had this happen.