CP Piston ring gap
 

Finally building my engine and wanted to check if there was a recommended ring gap other than what CP provides in their documentation.

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CP Piston ring gap
 

Depends on what your plans are for the engine.

On my first build I was planning on lots & lots of boost with 10.4:1 compression, so I went with larger gaps of 0.018" & 0.022"

On my second build I went back to stock compression and was shooting for lower boost, so went with smaller gaps of 0.016" & 0.018".

I have a 5858 looking for 500+ which is probably around 30psi.

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I can't give you hard numbers to use, but I'll lay some theory down for you:

Ideally a piston ring doesn't have a gap, as that's best for compression. However, as the cylinder, piston, and ring heats up, the gap closes. What you want is a gap as small as possible, but big enough so that when the ring is at its hottest, the ring ends don't touch. If they do, it could damage the cylinder wall, or crack the piston ring lands.

That said, Wiseco has a little calculation on their FAQ about ring gaps:

Attachment 215183

My numbers posted earlier were determined by talking to my machinist about my goals, and he made the call based on his experience.

My thought is something on the higher side close to what I ran on my first build would be what you want.