Like I posted...if your tune up is good you'll be ok. Oil is what seals the rings. The finer the finish, the less oil retention you have. All the way down the bore, meaning even at the skirts. It won't take much to wash the oil off the bore if your not careful. I would also be careful on start up. Wipe the bores with ATF until the paper towel comes out clean. Then leave the bores alone. A very light coat of engine oil, assembly lube (depends on the lube...I don't use anything with moly paste in it on Pistons) or 2 stroke oil on the piston skirts is all you need. Don't slop a bunch of oil on the rings. That will help with initial ring seal.NewbVetteGuy wrote: ↑Wed Dec 12, 2018 11:01 amThanks for all the replies!
I talked to the owner of the machine shop yesterday evening and he said that he doesn't know what Total Seal is talking about and this is just how he's been doing it for 30+ years and his race customers have no problems running 500 laps with this finish, so it should be good enough for a street motor....
I've confirmed that they definitely used a Sunnen 818 stone only it's even on my invoice.
For what it's worth, I'm looking to reuse my stock forged pistons with a 4.5 thousandths piston to wall clearance, and use a 1.2, 1.2, 3/16" ring set with spacers. Gapless steel top, napier 2nd, standard tension 20 lb oil ring.
-I'm mailing one piston to Total Seal to leave nothing to chance because as my forum name says I'm a complete Newb and I just don't trust myself to do anything fully right the first time.
Total seal recommended the cylinders be honed with 280 grit, medium pressure @ 50 strokes a minute with 3 full strokes.
Should I just buy a 240-280 grit aluminum oxide flex hone and go through each cylinder 3 times to try to get more depth on the cross-hatches to retain more oil, or am I better off leaving the cylinder wall finish as-is? It's a street car so longevity is kinda important...
(I'm honestly done with the machine shop; they've been nothing but trouble; they tried to give me someone else's heads back and tried to convince me they were mine, too... ??? The crank was polished beautifully, though.) -My options are:
1. Pay someone else to re-hone it
2. Run it as is
3. Flex hone it myself
Then keep the tuneup tight. You'll be fine. I wouldn't go back and undo what the shop already did.