Thread: Burned slugs 421 SB Stroker

Tweet

Using “pre-cut” rings is fine, however they should always be checked for ring end gap. File fit rings come way over size and a lot of filing has to be done. My first guess is that your gaps were less than .020 for your top ring and so when the engine warmed up and the rings expanded under full throttle, the ends butted together and knocked off the top ribs on two pistons. My second guess would be that you experienced pre-detonation and this caused the top edges to blow off. Finally, you might have had too much timing in the ignition and rattled the pistons apart.