Bill Brewer writes:
> The piston rings were very tight with no end gap.
> My two manuals list two different ring end gaps. My Bentley manual
> states that they should be .003" to .015", which is quite a spread. My
> Haynes manual has it a bit higher at .015" to .038". A good friend of mine
> suggests .010. He feels that tighter may cause the rings to break.
My guess is that the Bentley figure might be a typo. Typically, for a stock
engine, the low side would be 0.003" per bore inch. For an 86mm bore, that
would be 0.010". The outside, which I'd recommend if you're planning on
running the engine hard, is 0.004" per bore inch, or 0.013-0.014".
Sometimes, it's a good idea to gap to the high side of the spec for the top
ring, since it runs hotter than the rings underneath it. It's been a while
since I've pulled apart a wet-sleeve engine, but it always seemed that the
top rings were broken....
Cheers.
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