Whats the max you can mill a set of LQ4 heads? Exploring my options on this motor to see if I can get 10.5 easily or not. Was looking at maybe running some LQ9 pistons with the milled heads.

 

Bump.......

 

I wouldn't mill more than .080.Then I would check piston to valve clearance if you are planning a big cam.LQ4 and LQ9 are basicly the same.

 

No big cam, TR220 or TR224 was what I was leaning towards. Im not gonna have them milled too terribly much. I just wanted to know what the max was. .030-.040 was all I was gonna try for.

 

You'll be plenty safe milling .030-.040",you should make about 10:1 compression on a 6.0 block and still have good piston to valve clearance.

 

I have taken .060" off various LS1/LS6 castings with no problems. Just be sure PtV is checked if doing so with any cam of decent size. .030-.040" is not a problem.

 

What do you think the addition of the LQ9 pistons would put comrpession at then? Would a TR220 or 224 give too much lift with that combination?

 

If you go to the expence of building the block,spend a little more and add forged pistons.LQ9 are flat top stock pistons that would require dissassembling and honing the block.Why not do things right and do a .030"overbore with forged pistons.Then you can have any compression you want.

 

Im just thinking out loud. I want to do alot of things but financially cant do them all. I may just do the milling and some p&p and call it good. Plus the cam and such.

 

I think you'll be happy with the stock block,I just though that a cheap set of stock pistons,could windup being a lot more expensive than the performance gain would justify.