Ring gap.

[MercuryMan]

I laid my crank in tonight, turned my attention to checking ring gap before I called it a night. Right now I have .021" on the top ring in the one hole I checked. The paperwork with the sealed power moly rings doesn't mention gap specs. I checked the KB website, I have hyper flat tops, single relief. They recommend a .065" ring factor so with my 4.400" bore it should have a ring gap of .028"....Sound about right? Strictly track use, pump gas, 6000rpm max. Eagle H-beam rods. What is the easiest way to file the rings to fit?....I've never had to file them in the past on other projects.

[mario428]

With hypereuthictic pictons .028 should be about right, 2nd ring should be .002-.004 wider gap.

I use a small very fine file about 1/8 thick, clamp the end in my bench vise with the tang towards me. Grab the ring in 2 hands and squeese the ends against the file, pull towards you to cut some ring off, turn ring around every few strokes. Should only take a few strokes to fix yours. My rings were butted up out of the box and took about 15 stokes to get to spec. 2nd ring with no moly in it files a lot easier than the top one.

[MercuryMan]

Thanks for the tip Mario, I'll give it a try tonight. ;D....I've got a decent selection of flat files here and I have one that sounds exactly as you describe.

[MercuryMan]

It worked like a charm, thanks Mario. ;D ;D ;D....028" on the top ring, .032" on the middle ring. I fit all 8 holes and managed to get my pistons mounted on my new h-beams....Between the filing and the spiral locks my index fingers are aching....