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Discussion Starter · #1 · (Edited)
I bought an aftermarket camshaft for my pontiac 350 and i was wondering where i can find good aftermarket valve springs for my engine ( i can only find the springs for 389-455 pontiac engines at jegs) The cam specs are:

Cam Style: Hydraulic flat tappet
Basic Operating RPM Range: 1,800-5,800 RPM
Intake Duration at 050 inch Lift: 230
Exhaust Duration at 050 inch Lift: 230
Duration at 050 inch Lift: 230 int./230 exh.
Advertised Intake Duration: 292
Advertised Exhaust Duration: 292
Advertised Duration: 292 int./292 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.490 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.490 in.
Valve Lift with Factory Rocker Arm Ratio: 0.490 int./0.490 exh. lift
Lobe Separation (degrees): 110
Intake Valve Lash: 0.000 in.
Exhaust Valve Lash: 0.000 in.
 

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It has been a while, but I'm pretty sure the length of the 350 and the 400 springs is identical. As such, 400 springs should work just fine. Cams usually come with a card showing spring pressure and length, so if the spring meet the specs for installed height you should be fine.... Except: You've chosen a single pattern (intake and exhaust duration the same) for your 350. If it were about 218 intake, 230 exhaust, I think you'd be a lot happier. A 230 degree single pattern in a 350 with 110 lobe centers is going to require some interesting mods to support it. Too me, its the wrong cam for a 350 in a street application. As far as the spring are concerned, look at the the Crane beehive springs. Interesting technology that works.
 
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