Here is a link to the Deves piston rings installation instructions. Most
of the TR2-4 piston and liner sets are shipping with Deves ring sets.
http://www.deves.com/pistonrings_inst.html
They have a contact link on their site if you want to ask them for an
exact number for your ring gap.
Doug Hamilton
1960 Triumph TR3A
1963 Fiat Cabriolet
1967 Chev C/10
>Date: Wed, 17 Sep 2003 22:55:58 -0700
>From: "Randall Young" <Ryoung@navcomtech.com>
>Subject: RE: TR3 Ring Gap
>
>
>
>>> The piston rings were very tight with no end gap.
>>
>>
>
>Some rings are deliberately supplied slightly oversize, in case you are
>fitting them to worn bores.
>
>
>
>>> 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".
>>
>>
>
>Funny, my Bentley says only .003" to .010". My Haynes echoes this number
>(on page 15), but also specifies .010" to .015" for the TR4/A. Those are
>new clearances, I believe the .038" mentioned in the text is a wear limit.
>The TR4 factory manual also says .010" to .015".
>
>I'll also go out on a limb here, and guess that the original specs were for
>a different ring material, and that modern rings (meaning anything made
>since about 1953 <g>) should use the TR4/A specs.
>
>
>
>>> A good friend of mine
>>> suggests .010. He feels that tighter may cause the rings to break.
>>
>>
>
>I agree, .010" is a good number unless you're going racing. Then Mike P's
>suggestion of .014" would probably be a good idea, especially for the top
>ring.
>
>However, I doubt that going too tight will cause the rings to break, rather
>it will cause binding and cylinder wall damage. IMO, top ring breakage is
>usually due to the ring hitting the cylinder ridge, which can happen if the
>engine is revved beyond it's normal limit, even if that limit is below red
>line. IOW, if you've gone 30k miles without ever exceeding 4500 rpm, and
>then take it to 5000, you might break a ring.
>
>Randall
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