Is my ring gap too large?

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standup303

standup303

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This is my first time building an engine and am so close on piston ring gap I figured I would ask before exchanging them.

440 bored .030 over will be a street engine, 9.2:1

The book I have says compression rings .013-.025

Sealed Power says .004 for every inch of bore for a performance engine so 4.350x.004=.0174

My top ring is at .026
My bottom ring is at .030
Oil rings are .046 which is in spec per the book.

Do I need to exchange these for some tighter rings?
 
If this was a super stocker, or engine master’s challenge engine, or something where you will be tuning for the last 1-2 hp naturally aspirated I would say it’s worth your time to close them up. But for an average every day street/strip type of engine you'll never see any benefit to it. FYI I run ring gaps larger than most are comfortable with, the magnum I’m putting together currently is at .030 top and .035 second, getting it ready for lots of boost. They run absolutely fine off of boost with no more blow by than one set up tight. Don’t stress over it.
 
Better off with a wider ring gap, even if it seems ridiculous, than a tighter one.
 
Thanks all! Going to roll with it. Hopefully have a short block by end of the week
 
It sounds about right. A little wider is better than too tight. IMO
 
Agree. It will be fine.

But understand there is a reason that the gap is wider than spec. Likely, the bore is larger than spec, buy about 0.003". Your piston to wall is probably 0.005 - 0.006", verses 0.002 - 0.0025". Not a problem with your forged pistons, and good on a performance application where you don't want to give up anything. But you're pistons will be rattling around when cold.
 
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