[Zak]

I was told by a pro engine builder that gapless rings suck, he actually told me that they rob power! He didn't say how much power loss he has encountered or why, but does anybody have any experiences?

I wouldn't think one more thin ring on top will add up more friction.. but I'd appreciate any ideas.

Quoted: "Getting rid of the end gap altogether can also improve sealing, cooling and horsepower. Gapless rings eliminate the gap between the ends of the ring by overlapping slightly. Gapless rings are available in popular sizes with various wear-resistant face and side coatings. Some engine builders who have switched to "gapless" top or second compression rings say they've gained three to five percent more horsepower with no other changes." Source: Automotive Rebuilder

Also see Discussion on Gapless Rings