081 heads with a .480 lift cam
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From: Southern IL
Car: 88 GTA "Cocaine"
Engine: 350 tpi
Transmission: 700r4
Axle/Gears: 3.27
081 heads with a .480 lift cam
I heard from a fellow board member that I will have issues with the valve stem retainer hitting the guide with this cam
Basic Operating RPM Range: 1,200-5,200 RPM
Intake Duration at 050 inch Lift: 210
Exhaust Duration at 050 inch Lift: 220
Duration at 050 inch Lift: 210 int./220 exh.
Advertised Intake Duration: 264
Advertised Exhaust Duration: 274
Advertised Duration: 264 int./274 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Valve Lift with Factory Rocker Arm Ratio: 0.480 int./0.480 exh. lift
Lobe Separation (degrees): 112
the member did not say I would have issues to clarify he said I might
please if you have any info about this let me know
I suppose I could just grind down the valve guides a bit on my own but I would like some input before I take on more work!!!
Basic Operating RPM Range: 1,200-5,200 RPM
Intake Duration at 050 inch Lift: 210
Exhaust Duration at 050 inch Lift: 220
Duration at 050 inch Lift: 210 int./220 exh.
Advertised Intake Duration: 264
Advertised Exhaust Duration: 274
Advertised Duration: 264 int./274 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.480 in.
Valve Lift with Factory Rocker Arm Ratio: 0.480 int./0.480 exh. lift
Lobe Separation (degrees): 112
the member did not say I would have issues to clarify he said I might
please if you have any info about this let me know
I suppose I could just grind down the valve guides a bit on my own but I would like some input before I take on more work!!!
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From: Calgary, AB, Canada
Car: 1982 Trans-Am
Engine: 355 w/ ported 416s
Transmission: T10, hurst shifter
Axle/Gears: 10 bolt, true-trac, 3.73
Install the cam and find out. Don't pick a cam based on your valve train interference, pick the cam you want, then make the valve train work with it. It'll work a lot better in the end.
If you have a clearance problem, you'll find it while rotating the motor over by hand. You just stick something inbetween the retainer and top of the valve seal (or guide boss, depends if you're using positive seals), and measure the clearance. You want ~.060" at least, as a safety margin. .050" will probably work, etc... .025" is pretty dicey, and i'd get on fixing that. It's not like a bearing clearance though, you've got a fair bit of room to play here.
I've seen a lot of threads by you about cams/valves, wanna be a guinea pig and read an article I wrote? Perhaps it'll clear some things up, and you can tell me if I missed anything, or if something wasn't clear.
See sig.
If you have a clearance problem, you'll find it while rotating the motor over by hand. You just stick something inbetween the retainer and top of the valve seal (or guide boss, depends if you're using positive seals), and measure the clearance. You want ~.060" at least, as a safety margin. .050" will probably work, etc... .025" is pretty dicey, and i'd get on fixing that. It's not like a bearing clearance though, you've got a fair bit of room to play here.
I've seen a lot of threads by you about cams/valves, wanna be a guinea pig and read an article I wrote? Perhaps it'll clear some things up, and you can tell me if I missed anything, or if something wasn't clear.
See sig.
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