Im looking at a LSX short Block to buy hopefully,

They call this the, LSX Gen 1 Block....

Has anyone herd anything bad about these?

And why did they change the block after this one????

 

They still haven't fixed the core-shift problems and I wouldn't use it.

 

Is it my eyes or is there less material arround the left cyl than the right

 

Wow thats horrible!!!

 

WOW....just wow. I am really considering not using this block for my next build.

 

Yep!
That's unacceptable.

 

Well, I don't know if I would say never use one, but I would advise that any potential buyer have a block sonic checked to verify what was shown above is not the case for the particular block they are looking at.

 

I thought these GMPP LSx blocks were suspose to be "all that" for all out racing. Makes you think if you want to go big, RED or ELR are the only way to go.(with a modest budget)

 

hey guys i think you will find this cutaway has been prebore to different sizes.....
could robin @ chevrolet parts chime in to confirm or deny?
im using a second design lsx block and it checked out all good...
i could be stood to be corrected on first line though.
cheers dave

 

If you look at the picture, it appears you are correct. Look at the difference in thickness between the bores from left to right, right where the bores are closest to each other. These should all be the same thickness, when the block is bored to the same diameter in each hole. This particular one is obviously not, and no amount of core shift will change that dimension.

 

I never knew thats what they meant by "core shift" Good to know. LOL

 

Some people are idiots.... THis block was there display block at sema or something like that showing you different bore sizes with material left between the cylinders.

 

The possibility of core shift is a fact of life with any casting of this size and type and has been for decades. Molten iron is obviously not an easy thing to handle and is poured in without much finess and tends to push the cores around. Any block should always be sonic tested for wall thickness to ensure blocks with minimal or no core shift are used with big power. Same for alloy blocks though with cast in liners it is very obvious how far off centre they are.

This block isnt bad. There is still plenty of thickness along the major thrust faces. The left most cylinder which is max bored just accentuates the view of the thickness. The core at worst is 0.015 - 0.020 off. Thats nothing.

The early blocks that had trouble would break through with a regular 4.125" hole bored. That IS core shift.