Piston ring gaps
 

Can anybody give me some guidance on what to set the piston ring gap for 2.0S rings? Everything is Mahle if that makes a difference.

The factory workshop manual shows the ring gap to be 0.15mm (0.006") which seems a little small, not that I know more than the factory, only everywhere else I look they give a rule of thumb like 0.004" per inch.

http://forums.pelicanparts.com/uploa...1583450472.png

What gives? Do we run super close rings on early cars or did the factory have a misprint in their specs?

andy

The spec is 0.006 to 0.0177". So 0.006" is the minimum allowed.

I might ere on the loose side. An extra .01, .02 will have 0 effect on the compression. Too tight and they touch, the ring begins to twist or buckle and lose contact.

If the ring gap is too small it can pull the top of the piston right off. No, I'm not joking.

Looks like your using factory parts and using factory specs won’t give you any issues. The spec is not a misprint, the cylinders really do expand on these.

That spec is correct for air cooled cylinders.

.004/1” bore is for water cooled engines.

I did 0.008” gap on all. Just fine

Thank you. That was the part I was missing in all of this. Our cylinders expand way more than US domestic iron/steel bores.

All makes sense now, thanks all for your comments.

andy