im lookin at a ls3 block its a killer deal but ive been told that i shouldnt build a turbo motor with the block because its been bored to 4.080 i was just wondering if you guys think its safe to build a turbo motor out of it

 

anybody?

 

Strictly your decision... I've got an L-92 block that needs boring (my factory sleeves are so far off-center there's only 0.080" showing in places!) and I'm concerned about doing a NA build with it. I'm still cringing at the price for Darton dry's, so I may give boring a try first.

 

How much is the block you can get?

 

If it has a good true bore you will be fine. the newer blocks are alot stronger than ls1's and have many improvements.

 

Most of the LS3 blocks I have seen will go .020" over no problem. I would not go crazy with the boost on these blocks with stock liners regardless.

I have been sleeving quite a few LS3 blocks with Darton dry liners lately. Some blocks have the cast in stock liners not on bore center or vertical to the deck surface. This results in walls that are thick on one side and thin on the other. You would end up cracking the liner and the block if you run into detonation with your tune or with too much boost for the available octane.

Steve

 

We have to look really carefully at the LS3 blocks we use in our customers builds that's for sure. I've seen big hp from a LS3 block, but you have to be careful with them for sure. I bet I have 3-4 of them that will need sleeves from Steve before they can be run!

 

Are you guys still seeing this issue?

 

Still the same deal with these blocks in the LS3 family of blocks LS3, LSA, LS9

The new LT1 block hopefully will be better. It appears GM is using a casting method around the sleeves on these new blocks similar to a lot of the import blocks I sleeve. Import sleeve placement is far better than on the GM blocks to date.

Steve

 

Do you see this causing issues with NA motors, like stock sleeved LS3 builds or 416 strokers?

 

That is farther than I would allow any of our motors to go. We will allow for 4.070" max before it is nescessary for a sleeve. I definately agree with the guys at TSP above. Be careful with it, It is not impossible but not the best idea to use so large.

 

I know plenty of guys with 416's in NA and FI Ls3 strokers. You gotta take it to a shop that specializes in LsX's and the right rotating assembly. If you stroke it make sure you get a quality coated piston skirts because they do rock at BDC. But nothing that will zap longevity though, just precautionary.

 

One of the things we do @ TSP that nobody machining LS blocks can do is cnc digitize the blocks & determine bore locations relative to blueprint. When a typical machine shop bores a block they bore based on the existing bores location. GM never puts the bore in exactly the right location. What we do on blocks here is digitize the block & determine if it meets our requirements for being correctly machined to blueprint. if the block doesn't meet those requirements we send it back & get another block.

 

Jason, what exactly does that mean? Is it like a sonogram type thing where you can do a computer rendering of how the block is put together?

 

If I understand what he is saying properly, GM fails 99.9% of the time and the bore ends up off of center of the sleeve. They get it as close as they can if not dead center if GM was close with the original bore.