I have an ls1 block made in 99 with the stamp I can’t find this casting number 12553328 anywhere. Does this block have the thicker sleeves in it ? It needs a bore. Thanks for any info

 

I have not found that any LS1 blocks have thicker liners than before.
97-99 can't be bored more than .005" safely. After that core location got more precise but liners no thicker, so .005 still applies.

 

Block has low compression on some cylinders was in a dune buggy it’s scarred up but not deep 5 might fix it

 

Post a pic of the stamping number please.

 

 

If it's scarred up, it's a safe bet .005 won't do the job. You might find an aluminum 5.3 block and bore it to 5.7 size. That is doable..

 

Show us the block number also please. I have never seen a block with that number.

 

 

 

I agree with the +.005" possibly not cleaning up the bore. After all, that's only .0025" per side. However, in all my years in the shop, it still sometimes amazed me how much damage. 005" oversize can remove. Also this, even though purists may flame me to Hell and back:
It may be possible, depending on the boring equipment, to "shift" the bore centerline of the boring machine, perhaps .0015" towards the "worst" side of the bore, thereby removing more material from the most damaged side. Nobody in the real world would ever notice that minute amount of shift, and neither you, or a dyno, would show any difference. Just an idea, and, yes, I'd be willing to do it on my own engine, if need be. My opinion, YOUR engine.....

 

I ended up just lightly honing it out it had a few lines in the cylinders but nothing that could even catch a nail ordered std size pistons for it to save the block for future use

 

Glad to hear it!!

 

it is not mine for a customer I know it will run standard even with not perfect cylinders but there is a slight chance it won’t be good oversized so I figured it’s better the way it is now it had one piston that was coming apart out of a sand rail