I couldn't find any real specifics on the Olds VIN 9 camshafts for the flat-tappet 307s. So I decided why not just put it in one spot so it may be easier to find. Just in case anyone is looking for it for whatever reason.
Cam specs for the Olds VIN 9 cam are as follows (likely roller specs):
Advertised duration: intake 256, exhaust 268
Duration @ .050: intake 194, exhaust 210
Lobe seperation: 109
Intake centerline: 112
Lift at cam: intake .272", exhaust .274"
Lift at valve: intake .435", exhaust .438"
Timing @ .050" lift:Intake opens 15 ATDC, closes 29 ABDC
exhaust opens 31BBDC, closes 1BTDC
Found this on another site.
0.440/0.440 lift 196/208 @0.050 lift 109LSA for 83-85
256/270 109LSA
0.435/0.438 194/210 0.050 lift 109LSA for 86-90
Additionally, about the only close aftermarket cam that meets these specs are the Sealed Power CS-651 cam. Those specs I can find are as follows:
Lift at valve: intake .440", exhaust .442"
Duration @ .050: intake 194, exhaust 207
Lobe separation: 109
Keep in mind, these are computer cams. Can you get and use a bigger cam? Sure. Will it work with the computer? Try it and see. There is a limit as to what the computer can handle, but not sure where that limit is.
I can tell you the CS-651 will not kill your computer should you use it. I haven't used any others.
Valve Springs:
83-'90 VIN 9: GM# 22510372. These springs are also found in the Olds V8 diesels of the era, roller cam or flat-tappet, makes no difference. Specs below.
Spring Pressure @ 1.270": VIN9 203-217 lbs, the VINY 180-194 lbs.
Spring Pressure @ 1.670": VIN9 85-95 lbs, the VINY 76-84 lbs.
Spring free length: VIN9 2.090", the VINY 1.960"
Pushrod Length: 8.265" flat-tappet hyd. / 7.718" for the roller
Cam specs for the Olds VIN 9 cam are as follows (likely roller specs):
Advertised duration: intake 256, exhaust 268
Duration @ .050: intake 194, exhaust 210
Lobe seperation: 109
Intake centerline: 112
Lift at cam: intake .272", exhaust .274"
Lift at valve: intake .435", exhaust .438"
Timing @ .050" lift:Intake opens 15 ATDC, closes 29 ABDC
exhaust opens 31BBDC, closes 1BTDC
Found this on another site.
0.440/0.440 lift 196/208 @0.050 lift 109LSA for 83-85
256/270 109LSA
0.435/0.438 194/210 0.050 lift 109LSA for 86-90
Additionally, about the only close aftermarket cam that meets these specs are the Sealed Power CS-651 cam. Those specs I can find are as follows:
Lift at valve: intake .440", exhaust .442"
Duration @ .050: intake 194, exhaust 207
Lobe separation: 109
Keep in mind, these are computer cams. Can you get and use a bigger cam? Sure. Will it work with the computer? Try it and see. There is a limit as to what the computer can handle, but not sure where that limit is.
I can tell you the CS-651 will not kill your computer should you use it. I haven't used any others.
Valve Springs:
83-'90 VIN 9: GM# 22510372. These springs are also found in the Olds V8 diesels of the era, roller cam or flat-tappet, makes no difference. Specs below.
Spring Pressure @ 1.270": VIN9 203-217 lbs, the VINY 180-194 lbs.
Spring Pressure @ 1.670": VIN9 85-95 lbs, the VINY 76-84 lbs.
Spring free length: VIN9 2.090", the VINY 1.960"
Pushrod Length: 8.265" flat-tappet hyd. / 7.718" for the roller
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