real close to the lunati roller cam patrick suggested for my 88-4v 360 headed 318
lunati 60710 Voodoo roller cam with comp 901-16 springs
258/264
207/213@.050
108/112
.485/.485
not sure about the mag heads and GM spring
like patrick said..may be better to run the hughes springs and 2.2 retainers with mag locks
F.Y.I. on the pre mag heads the comp 901 spring is close on the lunati double spring specs that need machine work to run
comp are a single with damper,drop on with stock seals,covers any lunati SB cam flat or roller
comp specs are within 10 lbs of the lunati doubles and I have been 6200 with the roller cam with no valve float
comp 901-16
seat load 101 lbs @ 1.650"
open 242 lbs @ 1.250"
spring rate 353 lbs/in
coil bind 1.100
not sure of specs on the GM or hughes springs