Ok, this isn't particularly a buick question, its a question about head porting for turbo motors. I've got a turbo 388 stroker in the works, and i'm getting ready to start porting the heads. They are pro action 235cc runner with 2.08/1.60 valves. Current as cast flow is:
Intake Port Test Data @28" of water
.100 .200 .300 .400 .500 .600 .700
73.43 138.35 195.66 243.12 274.02 292.11 312.38
Exhaust Port Test Data @28" of water
.100 .200 .300 .400 .500 .600 .700
60.22 114.27 151.72 177.80 192.02 194.13 197.24
Our cam is a custom solid roller cam from comp, specs being:
280/273 advertised, 242/236 @ .050, .608"/.602", 114 lobe sep.
Now, i was told that smaller exhaust dur. was to provide for exhaust gas speed to help spool the turbo fast, but I think that if we have a turbo with, say, a .96 or closer to a 1.2 AR, then the sheer large displacment of the motor would be able to spool a turbo of that size, quite quickly even with a large exhuast lobe, but i don't really know. So, i dont know if i should port the hell out of the exhuast to get crazy flow numbers (230cfm @ .600) or just leave it moslty as is? I also plan on getting the intake to a little over 300cfm @ .600.
Oh yea, our power goal is 900hp @ ~ 15 psi with water injection and pump gas.
Intake Port Test Data @28" of water
.100 .200 .300 .400 .500 .600 .700
73.43 138.35 195.66 243.12 274.02 292.11 312.38
Exhaust Port Test Data @28" of water
.100 .200 .300 .400 .500 .600 .700
60.22 114.27 151.72 177.80 192.02 194.13 197.24
Our cam is a custom solid roller cam from comp, specs being:
280/273 advertised, 242/236 @ .050, .608"/.602", 114 lobe sep.
Now, i was told that smaller exhaust dur. was to provide for exhaust gas speed to help spool the turbo fast, but I think that if we have a turbo with, say, a .96 or closer to a 1.2 AR, then the sheer large displacment of the motor would be able to spool a turbo of that size, quite quickly even with a large exhuast lobe, but i don't really know. So, i dont know if i should port the hell out of the exhuast to get crazy flow numbers (230cfm @ .600) or just leave it moslty as is? I also plan on getting the intake to a little over 300cfm @ .600.
Oh yea, our power goal is 900hp @ ~ 15 psi with water injection and pump gas.