helga203

Friend is new to ls world. Has a 6.0L engine with aftermarket heads with stock 65cc chamber 10.1 compression with .660 springs. I'm not talking him out of it or explaining cam specs. He just wants to know what is max lift that he can get away with from real world experience. He's looking at ..640 to .650 lift. Drag car only. Thx
P.S. Engine is assmebelled already just wnts to change cam he's mid .500's lift now. He want high range of the rpm since it's only Drag race. NA engine. Thx

stevieturbo

That would depend on many other things, and if it's high rpm he wants then max lift is certainly not what he wants.

Milan

Helga glad to see you are still around! I have seen people running that high before but can't comment on it's effectiveness

stevieturbo

I'm sure a lot will depend on whether his valvetrain comb cam handle such lift, and whether his head/intake package would even benefit from it too.

Nevermind PTV which would also become an issue with higher durations/overlap.

BLOWNBLUEZ06

Cam specs are are more about valve timing. Choose the lobes you want to run and the valve timing you need and the lift falls where it falls. Of course, that's as long the lift doesn't go beyond your spring specs.
If you're wanting to run the maximum lift based on a given set of springs, it'll be important that you verify the actual installed height and coil bind of each spring as well as verify the actual yielded rocker arm ratio. Once you get those values, you can work from there.