Overbore all 6 or sleeve one cylinder?

[Brian Mc]

Ok, i have all of the parts to put my engine back to stock (rings, good bores, and good stock pistons) but i have one cylinder that from the factory was either out of round or sized wrong. you see the ring gap is good on all cylinders but one. it is .031 when all the others are .020. so it had blow by, low compression, and knock.

1. i have heard that stock GM pistons are the best for street use and I noticed the steel reinforcements. I want a quiet engine, and it will only see medium street duty. are there good replacements available cheap?

2. it's cheaper to sleeve #1 cylinder instead of overboring, new pistons, machine shop to press them onto the rods, and new rings. Sleeve or overbore?

 

[JayC]

Its cheaper to sleeve the one cylinder.

Personally, if you have confidence in your machinist then I would have no problem running a sleeve. Add to that the fact that you really havent had anything catastrophic happen to the block so there is nothing funky going on behind the sleeve. That's even better.

Now.. The bigger picture. If you have serious performance aspirations, it may be better to suck up the cost and get some forged pistons. Granted, not the best for street duty but totally usable nonetheless.

If it's more or less a stock rebuild and nothing faster than mid 11s is your goal, sleeve it and don't look back.

 

[SPECTRA PREMIUM]

Sleeve it...

 

[Brian Mc]

is that true about the stock pistons that they are the best for light streetuse? and are they discontinued GM?

 

[S2V6RACER]

Originally posted by Brian Mc
is that true about the stock pistons that they are the best for light streetuse? and are they discontinued GM?

I guess I don't understand your question. They are the best piston for street use no doubt, but you do not specify what kind of HP level you are going to be pushing when you are off the street. Stock pistons are reliable in the 10's but they are heavy. Last I heard stock pistons are discontinued.


Ted

 

[Brian Mc]

i screwed that up, i meant somewhat heavy street use but no track use. i probably won't go larger than a TA49. I just hammer the car from stoplights 2 or three times when i drive it for 30-45 minutes. Burnouts, that sort of thing. if they are heavy pistons is there a lighter available?

 

[KendallF]

The stock pistons should be fine for what you're after. As somebody else replied to your other thread, you should at least consider getting the block lightly honed if you sleeve that bore. No sense in wasting your new rings.

Pretty much any forged piston will be lighter. The TRWs come with a heavy pin to get the weight close enough to the stockers to avoid a rebalance. If you use a lighter piston you'd need to get the assembly balanced, which will add another $150-200 to your bill.