What ring gap are you running?

KingColt said:

I was just thinking about opening up my stock rings to about .025-.028 from the stock .019 or so

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Generally speaking, many engine builders widen the ring end gaps, to help reduce friction.
Others widen the ring end gaps so as to avoid ring butt.

Unless one of these engines was damaged via self detonation, or
overheating issues, I have not witnessed ring butt in these engines.

For what reason are you considering doing this?

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I see from your signature line that you have a nice build..

A couple of other questions:
Still a 376 LSA?
What is your compression ratio?
What Fuel?
What are your normal IAT's?
Any engine cooling issues?
What engine rpm are you shifting at?
Any Dyno Numbers?

Is Justin still around?

Cheers

KingColt said:

I've just seen a lot of LS engines fail from ring butt. When other it could have been a perfectly good motor if not for that.
I'm nearly fully built and over boosted.
I have the engine in the machine shop right now getting refreshed.

So I wanted to open it up just to avoid possible failures while I'm already here.

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-assuming the ring end gap is correct for that ring set-
Cylinders, may times wear more at the top, then at the bottom

If your cylinders are all straight and round, and you have the correct ring for your application, you should have no problems with rings butting, and breaking.

Tapered cylinders and excessive heat, in my opinion, are the main reason for rings to butt and break.

We have all seen pictures on this forum, where the top ring and ring land lifted off the top of a piston.

This is from excessive heat, normally generated from self-detonation.
And this is especially so of the two rear cylinders, which tend to run hotter than do the others.

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Ring end gaps can vary from one piston ring manufacturer, to another.
Too large a ring gap, and the rings might flutter, and not seal.

This was exactly why the gas ported piston was invented.
We wanted less ring tension, to reduce friction, but did not desire for the rings to flutter.

Personally, I don't think you would run into any problems by increasing the
top ring end gap by maybe 0.005", and the second ring to maybe 0.008".

More than that, and I would suggest you contact the ring manufacturer, and speak to them.

They will most likely have a formula for their rings, which you can use,
or maybe even suggest a better ring for your application. . .

Cheers