turboal1

what's the rev limit on the Pac 1219 valve springs
set to specs ? under .600 lift cam.

07NBSChevy

I would say around 6500 Rpm with an 1.800" Installed Height. They have a max lift of .625. I don't know if PAC actually lists a Max RPM on springs since there is so many variables that can affect that.....Cam Lift, Duration, Valve Weight, and so on.

I have run the 1218's up to 6500 rpm, but usually have my shift RPM set at 6,300 rpm using a small 212/218 .552/.552 113+2 Cam. I am using C5Z LS6 Hollow Stem/Sodium Filled Valves in my 243 heads. I am also using the PAC-R511 Titanium Retainers and Machined Valve Locks to keep my valvetrain as light as possible.

randeez

used pac 1219X on mine, 218/228-600/600 cam with ls3 hollow intake valves. have ran it up to 6700 before but cam is done by then, shifts are set at 6500 now i think

turboal1

I think there giving up at 6800 on me on the street.
on the dyno they revved to 7000 ok.
when installed with the cam.and tuned.