Weird - Oil ring pops out of groove while running on dyno

[swamp rat]

Originally Posted by Kennuck

You are exactly right hamjet, that's why I asked if it was stroked. It seems to me the only way this could happen is if the oil ring is coming out of the bottom of the bore on the downstroke.

I'm with you and Hamjet, i would like to see this ring after it comes out the bottom.

Also if it does come out the bottom then the cylinder should show some kind of damage, the thickness of that bottom ring is thicker than the boar to piston clearance, it should be catastrophic. Bore to spec, proper piston, it should show damage of that is infact happening.

A block clearanced for a 383 stroker would have the machining perpendicular to the wrist pin, even if it came out there it would still show some damage.

I keep thinking look inside the piston bottom and ring groove for a casting flaw? but you would think the piston would have a catastrophic failure..