Comp cams 12-673-4 solid flat tappet
247 (I) @ .050
254(E) @ .050
.504(I) lift
.498 (E) lift
Lsa 112
Comp recommends valve spring #986-16
Installed height 1.75
Spring rate 322
Seat pressure 132
Or
987-16
Installed height 1.8
Spring rate 370
Seat pressure 139.5
Using 1.52 ratio rockers, I come up with 296 and 328 open spring pressures.
My engine builder suggested I use a spring with 354 open pressure and the tech from comp cams suggested a spring with 335 open pressure.
With no exotic light weight valves and valve train, what are your thoughts on open spring pressures?
247 (I) @ .050
254(E) @ .050
.504(I) lift
.498 (E) lift
Lsa 112
Comp recommends valve spring #986-16
Installed height 1.75
Spring rate 322
Seat pressure 132
Or
987-16
Installed height 1.8
Spring rate 370
Seat pressure 139.5
Using 1.52 ratio rockers, I come up with 296 and 328 open spring pressures.
My engine builder suggested I use a spring with 354 open pressure and the tech from comp cams suggested a spring with 335 open pressure.
With no exotic light weight valves and valve train, what are your thoughts on open spring pressures?