View Full Version : LS1 cylinder wall thickness question

03-13-2012, 02:06 PM

I'm looking to buy a used LS1 corvette block from a buddy; but in doing some reading I found that there are two variations of the cylinder wall thickness.

Is it true that the later model LS1 blocks have thicker cylinder walls?
If so, can someone tell me the casting numbers which would reflect the thicker cylinder walls?

Just want to make sure I know what I'm buying before I commit.

Thank you!

03-13-2012, 03:14 PM
I dont have casting numbers. but

97-98 Can only be Honed to 0.0040"
99+ can be bored 0.010"

Otherwise it needs a sleeve.

:Google: for engine block casting #'s but your going to see 97-98, 99+, and LS6 and the LS6 is same as 99+ in that aspect.

If your real worried, take it to a shop to verify.

03-14-2012, 03:18 AM
I've always went on 3.903 on 97 to mid 99 blocks and 3.905 on mid 99 to 04 blocks. Otherwise it needs a sleeve.