I pulled my 5.3 apart and was going to put new pistons and rings in and discovered a couple light scratches in the cylinder wall. Soooo I am wanting to take it out to a 5.7 and put some nice parts in there. I am not sure on what size pistons to go for, I saw some 3.905" on Texas Speed. Should I go for 3.900" instead? I am wanting to build it forged so it can take nitrous/supercharger down the road. What are some good pistons and rods? I don't want to spend an arm and a leg but would like some quality. Thanks

 

Compstar Rods

Wiseco Pistons with SteelTop/Napier 2nd Ring Set

Those should do the trick without breaking the bank!

 

i was wondering if something like this would work in the 4.3 as well?

 

as far as boring it out, try to start at the standard ls1 size. make sure you have the block sonic checked too. it the walls get too thin, forged pistons wont do you any good. i have heard a few guys who have done it before had overheating issues from thin walls. just some things to think about while your in there

 

you can bore any engine but a 4.3 has a 4" bore 3.48" stroke as it sits. I don't know the costs of new pistons/cranks for them but I'd buy a 5.3 before I bothered doing anything to a 4.3

 

x2!!!

 

mahale makes a 3.898 piston for the LS1 which is a drop in piston for a light hone. So you could save a little more cylinder wall material left. Its what i just bought. they are -4cc coated flat tops with valve reliefs.

 

no problems here with my 5.3 to 5.7 combo. I went the mahle piston route with eagle rods and stock crank. no overheating problems and it makes pretty decent power.

 

Those numbers in your sig are great. I cant wait to see what my combo will do. hoping to push 15psi on mine.

 

Hey '06, did you have to rebalance your 5.3 crank with 5.7 pistons. I've heard a few times that the 5.3 crank has a different balance than the 5.7 crank. Any issues? I have a 5.3 motor and want to go 5.7, but I also have an LS6 crank that's been micro-polished and had the oilholes chamfered. Anyone know whether to go with the LS6 or just reuse my 5.3 crank to save from any differences between the cranks, ie: balancer, flywheel, reluctor ring, etc.....(HIJACKED, Sorry)