LsX build

[2SS45th]

Originally Posted by Unreal

And cheaping out on skipping a little machine work that will probably still be needed when building a $6k+ short block isn't the best idea. All the machining will have to be checked and cleaned up anyways.

When you're talking 15 to 20 grand long blocks, a thousand in machine work is nothing. Find a machine shop near you that specializes in racing engines or have a trusted shop build one and ship it to you. It kinda sounds like this might be your first engine build, so I'd find someone that can help you along the way or do it for you. But there is no way to do this without a machine shop, even with all brand new parts and a "finished" block. Most piston sets out there are 4.07 bore anyways.

[Pro Stock John]

LSX blocks are iron and you'll be adding at least 80 lbs to the car, don't recall the exact weight increase.

If you were looking to go in the 8's I'd see doing one, the 6 bolt design will give you more clamping force, will do a better of keeping the heads from lifting under high cylinder pressure.

In the 4th gen days we went 6 bolt when the cars were going low 8's and quicker. 5th gens are over 500 lbs heavier, sometimes like 900 lbs, so I'd say anything in the 8's I'd think about it.

9, 10 second car, I don't see the need.