Input on spring pressure for ls3 stroker
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Joined: Mar 2018
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Input on spring pressure for ls3 stroker
I'm seeing an issue with power rolling off early, 6300 rpm. Car's on a hi-ram, no air restriction on intake side, heads are capable of moving a lot of air also. I'm thinking it's a spring pressure/valve float issue. Anyone able to share a recommended spring pressure for an ls3 based 417 stroker that's at about 13:1 compression and spinning to 7400 or so? Cam is:
In./Ex. Duration242/258
In./Ex. Valve Lift
.646/.637
In./Ex. Duration242/258
In./Ex. Valve Lift
.646/.637
Safety Car
Joined: May 2006
Posts: 3,691
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From: Potomac MD
What springs are in there now? I presume steel valves how about rocker arms GM or adjustable or roller tip ones etc. What lifter do you have in the motor - OEM, Johnson regular - limited travel etc. Pack 1207x might be an answer but we need to know the details here. The 1207x is a 155 / 450 or so on the nose.
Thread Starter
Advanced
Joined: Mar 2018
Posts: 52
Likes: 14
What springs are in there now? I presume steel valves how about rocker arms GM or adjustable or roller tip ones etc. What lifter do you have in the motor - OEM, Johnson regular - limited travel etc. Pack 1207x might be an answer but we need to know the details here. The 1207x is a 155 / 450 or so on the nose.
Last edited by hearno; May 7, 2026 at 11:36 AM.
