Just wanted to see if anyone has heard of such. Got my new issue of GMHTP the other day and they showed a road race 422 build that supposedly used an LS3 block punched out to 4.1 with a 4.0 stroke. They just punched it out .040 without doing any trickery to make it work . This was an endurance type of build making 700+HP. I was under the impression that a light bore cleanup was as far as the block would safely go.
Im running a stock displacement LS3 and planned to build a 416-418 down the road when I got bored with the setup. If I can safely go out to 4.100, I will ! If the block will take it, Im a fan of the bigger bore, just for the increased head flow.
What gives? Is it legit?

 

Resleeved it can be done. I am looking at a Livernois Big Bore block for my next build. They are just one of several companies doing this.


Travis

 

Looking at the liners in my factory bore L92 block, I'd say no way. On this block, the liners are cast in slightly off-center resulting in one edge of the liners being < 0.060" and the opposite side being ~ 0.120"...

 

People have in fact opened them up to 4.100. Caution needs to be taken in the core used but it has been done. There only removing .0175 material per side so a little core shift is ok.

 

Yea, from what I gathered from the article, no sleeve work was done, just torque plate bore job on a factory LS3 GM block. What got me was, this isn't a 1/4 mile at a time build. It a road racing deal that sees a lot of RPM for extended time. Brutal conditions for a thick wall block, much less a max bore factory block. It gave me the impression the factory block is stouter than it gets credit for.

 

GM started making the liners thicker with the LS2. They state that you can bore them +.020 and plenty have gone +.030 over.

 

Interesting thing in the video is that they did not run coolant during the boring process.

Was that just for the video or do they use no coolant in the production process?

 

4.100" on a ls3 block is definitely not ideal.

 

Im glad someone that does this all the time has chimed in. Jason, have you done any experimenting with a 4.1 bore? Is it something that would only be a good idea on a select core? Or not advisable at all?

 

It smells of " you need to sleeve that block to get that bore"$$$$$$$$$!

 

Thread resurrection for updated info. Max bore/stock sleeved LS3/L92's are becoming more popular.

https://ls1tech.com/forums/generatio...92-engine.html