COVi

Hey everyone, I am new to the LS1 world and dont know too much. I plan on building a LS1 for a school project and wanted to start with a used block, mainly for price but also to do the machining on it myself. My question right now is when looking at used LS1 blocks, what are some things I should be looking for? Are there any numbers I need to look at, or certain places on the block that might be broken? Any advice would really help.

Jon@Texas-Speed

iTrader: (18)

I would try and get the newer of the blocks if possible as they will have a little more material in the sleeves. Also, just be sure to inspect the sleeves well for cracks or anything like that. Remember you can't really bore the LS1 aluminum blocks. You are limited to a .005-.010" hone to maintain sufficient material in the bores. Also, make sure there are no cracks around the bolt holes or starter area. If that stuff looks good, I would say it is fine to use for your build. Let me know if you have any other questions!

Jon

COVi

If I plan on re-sleeving the block the bores are not that critical are they?

garygnu

it would be cheaper and easier to find a 5.3 block and bore it out.

COVi

A 5.3 is a iron block, correct? Can an 5.3 make it out to 427ci? Say 4.125" Bore.

Also, I plan to do all or as much work on the motor myself as I can and dont need it done anytime soon (I got 2 years in school) so I can save up and do a motor right.