inmotion5939

hey guys, i'm in the process of rebuilding my 997.1 m97 engine which had 110k miles on it when pulled. with that said am replacing all bearings, gaskets, seals, etc and was curious regarding piston rings ...

i'd like to replace mine however am curious as to whether or not honing will be needed afterwards for a proper "seat" if you will ... the cylinders are lokasil and don't believe such can be easily honed if at all. i have differing opinions regarding such and was curious from anyone w/ experience doing so or an expert opinion on here.

also, please save me the nickies/je pistons talk, i'm doing a rebuild on my own terms and replacing what i a.) think NEED replacing and b.) what i've budgeted for ... i understand dong it once and right at that however can't see boring/sleeving a perfectly good block especially given my current affairs (*cough* proposing later this month *cough*).

AWDGuy

I know you dont want to go down this route, but I didn't read anywhere on how you are sure the cylinders are not tapered and round enough to not cause issue with new rings. The info I've read on re-ringing this engine is you use the existing rings because the cylinders do taper in these engines.

And from what I understand, no these cylinders just cant be honed out.

Iceter

It's not a matter of what we think, you have to do what the ring manufacturer says you should do for the rings to take a good seat in the bores. What is the recommendation of the company that makes the rings?

Just out of curiosity, those bores look pretty good from here. Obviously, a micrometer is worth a thousand pictures, but what necessitated the rebuild? If the bores are good enough that you think you can just install rings and not have to worry about resurfacing the bores, then why did the bottom end have to come apart?

sober_owl

its common practice to rehone so new rings will seal better...ur best bet send pistons with block to a machine shop n let them check your cylinders for out of round.. check deck for warpage maybe resurface both heads n block for better headgasket seal..

short answer...rings will just take longer to break in if you dont rehone..

Chris(MA)

If I were in your shoes and my cylinders were in good surface condition, I'd have them straightened and top rings added to keep them from ovalizing.

Seems like cheap insurance considering you have everything in pieces