To all you engine builders......
Do you have a favorite piston ring brand ?
Thanks, Mike
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childs and albert zero end gap
Depends on what the engine will be primarily used for. For a street engine up to 6000 rpms, any premium moly-filled top ring. A good moly ring on a smooth cylinder wall will 'break in' within 100 miles of ordinary driving; no fancy gyrations or oils needed like in the old days. Some can be broken in with 2 full pulls on a dyno during final tune.
Note there are TWO 'moly' rings available in ring sets. One has a fairly deep machined groove filled with molybdenum alloy, while the cheaper 'moly ring' is plated with the same stuff. Both need a smooth cylinder wall but especially the coated rings. A rough surface cylinder wall may wear thru the thin moly-plate before the ring is fully broken in. 600-rms smoothness is whats usually specified for all moly rings. If the ring is moly-filled, the sales literature will say so; if nothing is specified, it's likely moly-plated. Durability will be better with moly-filled rather than plated.
I suggest staying away from stainless steel top rings- they're made for very high-powered engines to combat detonation or for abrasive dirt track racing, are expensive and don't break in quickly. Also stay away from plain cast iron; technology has moved on to much stronger, more durable rings. It's also interesting to verify where the rings are manufactured; China, India, Mexico and other off-shore mfrs sell 'performance' piston rings under some U.S brand names.
Note there are TWO 'moly' rings available in ring sets. One has a fairly deep machined groove filled with molybdenum alloy, while the cheaper 'moly ring' is plated with the same stuff. Both need a smooth cylinder wall but especially the coated rings. A rough surface cylinder wall may wear thru the thin moly-plate before the ring is fully broken in. 600-rms smoothness is whats usually specified for all moly rings. If the ring is moly-filled, the sales literature will say so; if nothing is specified, it's likely moly-plated. Durability will be better with moly-filled rather than plated.
I suggest staying away from stainless steel top rings- they're made for very high-powered engines to combat detonation or for abrasive dirt track racing, are expensive and don't break in quickly. Also stay away from plain cast iron; technology has moved on to much stronger, more durable rings. It's also interesting to verify where the rings are manufactured; China, India, Mexico and other off-shore mfrs sell 'performance' piston rings under some U.S brand names.