thorinZ28

I have an ls1 that bent two connecting rods and I've found a set of stock rods and pistons(same year and motor) from a friend that are in great shape he just went to forged because he went supercharged ,my question is can I use his rods and pistons in my motor with my crank without having to balance the rotating assembly ,I figured since there all factory parts just like what I removed that I could put them in without balancing and I'd be ok but I'd like to here some opinions on this,I can get the assy balanced by a local machine shop but Ive read the factory pistons and pins don't like being pressed together other than at the factory so I'd hate to have them pressed apart and then back together to have the assembly balanced and then have a pin walk out of the piston

mark21742

My personal opinion is rebalance any time you change a part on the rotating assy....cheap insurance to save a motor from deadly vibration.

redtan

iTrader: (5)

Balancing is not done to certain parts all the same, it's done on an individual unique set of parts on hand.

So just because his ls1 rods and pistons were balanced to his ls1 crank doesn't mean that those ls1 rods and pistons will be balanced with your ls1 crank.

You'll have to rebalance.

Grimes

iTrader: (3)

You need to have the whole assembly balanced, that's the right way to do it.

thorinZ28

Ok thanks for the input guys , has anyone else hear of or had a problem with pressing the pins back on stock ls1 pistons? Or having a pin walk out after they did it? That's my main concern at this point because as of now I have a good set of rods and pistons and a good crank to use and I'd hate to take it and pay to have it balanced and then run into pin problems.I guess I could buy new pistons but I'd really rather not since these are in such great shape

RonSSNova

iTrader: (3)

There are no balancing pads on the rods to balance with......correct?
I'd bet it's close enough.

SuperSport01

The factory has tolerances on rod and piston weight. Do you really think the factory has time to balance every engine on the line? NO. They know what the rod and piston assembly weighs before the assembly even gets near the motor. So I say yes you can use them as is. I would however try to use the rod and piston out of the same # cylinder as the ones you have to replace, just to further ensure they'll work.

That being said, having the engine balanced will always come out better.

garygnu

from what I have read ,cracked rods should be machined if the cap is removed.you should have your rotating balanced .get new rod bolts and machine the rods.