Got a LLSR cam from cammotion in my 5.3 twin turbo setup. 8000 rpm shift, 25 psi. 650 lift. I originally had PAC springs with 200 seat pressure (1237x) in it that worked good. Went to change my springs and was going to put these same springs in but now I see they are not recommended for the street. Was going to do some street driving this year due to tracks being closed. Cammotion recommended a spring with 160 seat pressure, 500 spring rate, 1.000 coil bind. Does that seam a bit weak? I could probably shim them to 1.720 installed height which would be 200 seat pressure. Not sure if that would be to hard on the spring then? I think the cammotion spring is a PAC-1209.