Hey guys, I'm building an LQ4 setup with a 76mm turbo, my question is: I just recently bought a cam 216/220 cam (here are the specs: 54-414-11 - XFI RPM Hydraulic Roller Camshafts ) and some new LS6/LS9 springs. I read somewhere that some people are shimming the springs to increase seat pressure for boost, what would you guys recommend on my setup? The cam is only .525 lift and the springs are good for .570ish.. Also, where can I find the correct shims? Thanks guys!

 

Anybody??

 

Without a spring mic and bench pressure gauge I wouldn't worry about it, imo

 

Well I just wanted a little more seat pressure to insure there's no valve float with having the bigger LQ4 valves and some boost. But I'm prob not gonna push it higher than 12 mabe 14 psi. Mabe I'll be fine.

 

dual springs and move on. IMO

 

A stock gm valve spring will far out last a stiff aftermarket valve spring and be more reliable too. Never heard of a broke ls6 or ls9 spring but you can read for hours of horror stories with aftermarket springs braking. I wish I could use a ls6/ls9 spring but theres no way with my higher boost.