piston ring end gap

[flextrainer]

Hey guys just wanted to check and see if you think .014"and .016" top and bottom ring end gaps are too big. I was thinking they should be more like .007" and .009" for a 47mm bore. Don't know the piston to bore clearance, but it came this way from the manufacturer.

[kliff]

Nov 15, 2009 19:12:43 GMT -5 flextrainer said:

Hey guys just wanted to check and see if you think .014"and .016" top and bottom ring end gaps are too big. I was thinking they should be more like .007" and .009" for a 47mm bore. Don't know the piston to bore clearance, but it came this way from the manufacturer.

As a rule of thumb, I go .004" gap per 1"(25.4mm) bore, rounding UP on the bore.

So your 47mm bore rounds up to a 2" bore = .004" x 2 = .008" MINIMUM.

It came with a .007 and a .009? I'd leave the .009 alone, and open the .007 to .008, and call it done. IF you plan on racing, with a limitted break-in, do your math, and add .001"

Hope that helps ya some.

[felliott]

On all of our engines ( small ones to very large ones, stock to race) we use .004 per inch. No problems in 50 years.

[flextrainer]

That's exactly what I thought I've always used that formula, so I didn't know if they were larger gaps for some reason. They came out of the box at .014" and .016".