66vert

iTrader: (3)

Hi there,

I read somewhere that the earlier LS1 blocks 97-98 can only be bored .005-.010" because of thinner wall liners. Plus they do not have the oiling capacity of the 2000 and up blocks? Anyone out there have a performance rebuilt 97-98 LS1 please chime in. thanks

redtan

iTrader: (5)

Most LS1s get bored out to 3.903-3.905 so yeah that's about the limit of those sleeves.

JakeFusion

iTrader: (7)

The 01+ blocks were LS6 blocks with better oil flow. This is true.

The most I'd take any of the LS1/6 blocks out to is 3.905" but you should be safe with a 3.903" allowing for one additional rebuild if needed in the future.

66vert

iTrader: (3)

New to LS engines so I appreciate the advice.

Typical SBC overbore pistons are .030 Sounds like newer engines wear less so is a typical overbore piston size .005?

JakeFusion

iTrader: (7)

Most piston sets can be ordered .003" or .005" over. If the block is in good shape and can get by with less, I'd do the minimum so you have enough left over for a rebuild down the road.

redtan

iTrader: (5)

That is still true for current iron blocks...not so much for aluminum ones.

moeZ28

iTrader: (7)

The LS1 is an aluminum block motor with cast iron sleeves...the thickness of the sleeves is what limits the max overbore on these motors. Ive always heard 97-98 LS1's can only tolerate a .005" overbore max. I know Mahle makes the stock pistons and also makes a 3.908" bore forged piston for Ls1's which I ran in my old car. It was a 98 Z28 but the block was a 2002. I can attest that the later blocks can be bored .010" over with no issues. Not all 2001 -2002 blocks are LS6 blocks...only a small percentage are.

PREDATOR-Z

Guys you do not bore .005, you hone

ls1 1990 VN

Haha! Pred

I now run the Mahle 3.908" pistons in my early LS1. It has been at this hone now since 07, occassional road race, drag etc

bww3588

iTrader: (49)

3.903 on 97-early 99 blocks. 3.905 on later blocks. Good rule of thumb. Can you go bigger? Sure. But no reason to go any further than you have to.