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oversized piston rings

yubh8tn

Well-known member
Joined
Aug 21, 2019
Messages
165
Location
coeur d alene, idaho
Hello guys, it took me a while, but I finally figured out the issue with my old rings. Block was bored out by .50mm sometime in its existence, hence the non-fitting factory rings.

The issue now is finding oversized piston rings. I can find ring/piston combos and rings for 2g's but not for our engines. Does anybody know where to find correct thickness 0.50mm oversized rings?
 

iceman69510

Turn Right Racing
Staff member
Joined
Mar 5, 2001
Messages
10,907
Location
Michigan
It notes down below in the ad that you can request oversize.

Doesn't specifically specify NPR rings, but this seller, Domestic Gaskets, does have NPR in other auctions. You could ask them.

ring set

Andrew, I think the ring heights are different between 1g and 2g pistons (thinner low friction rings in the 2g). Not 100% sure that is correct, but that is what I recall.
 

slugsgomoo

Well-known member
Joined
Oct 16, 2003
Messages
3,737
Location
Tacoma, WA
It's possible... to be honest I haven't seen an OEM piston in almost 15 years so... /ubbthreads/images/graemlins/laugh.gif
 

yubh8tn

Well-known member
Joined
Aug 21, 2019
Messages
165
Location
coeur d alene, idaho
Thank you guys for the replies. I contacted those Domestic Gaskets guys a few days ago, before making this post actually, but their only oversized ring set for our car was made by Evergreen and they wanted $100 for them. I don't think Evergreen is a good brand but correct me if I'm wrong.

Does the ring thickness matter? What are the correct ring thicknesses for our engine? On my last post somebody said 1.5mm, 1.5mm, 3.0mm, but I can only find 1.2mm, 1.5mm, 3.00mm on Ebay. Will the difference really matter (if any at all)?
 

iceman69510

Turn Right Racing
Staff member
Joined
Mar 5, 2001
Messages
10,907
Location
Michigan
Yes, it matters alot. If the rings don't fit the grooves, they will not fit (if too large) or will not function as required and likely break (if too small).

Those numbers seem right, as I recall the 1g top rings being thicker.

I don't know anything about evergreen. I'll look again when I have a chance.
 

yubh8tn

Well-known member
Joined
Aug 21, 2019
Messages
165
Location
coeur d alene, idaho
My first piston ring groove looks a bit smaller than my second so I went ahead and ordered some NPR 1.2mm, 1.5mm, 3.0mm rings as that's the brand I want to go with. I'm gonna figure out a way to measure the grooves before they arrive just in case. Thank you guys for helping me figure this out. Almost there!
 
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