Valve Spring Shims
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Joined: May 2010
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From: Saskatchewan, canada
Car: 1982 Firebird T/A
Engine: 305
Valve Spring Shims
Anybody ever installed them? Seen then in the JEGS flyer, with "Cooling" louvers. So they are supposed to add a little more tension in assuming?
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Joined: Jul 1999
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From: 51°N 114°W, 3500'
Car: 87 IROC L98
Engine: 588 Alcohol BBC
Transmission: Powerglide
Axle/Gears: Ford 9"/31 spline spool/4.86
Re: Valve Spring Shims
They're used to get the proper spring install height. Adding shims to spring height that hasn't been checked may lead to coil bind since you're shortening the install height.
My spring pockets are deep and I have longer than stock valves to allow taller springs for more valve lift and spring rate. I use spring guides under the springs and shims under the guides to get the recommended install height for the springs I use. The triple springs for my BBC have around 800 pounds open pressure and around 300 pounds on the seat. With 0.800" lift, I don't want valve float at 7500 rpm.
If your valve springs are weak, adding shims won't help since they'll probably create more problems. If your springs are weak, replace them.
My spring pockets are deep and I have longer than stock valves to allow taller springs for more valve lift and spring rate. I use spring guides under the springs and shims under the guides to get the recommended install height for the springs I use. The triple springs for my BBC have around 800 pounds open pressure and around 300 pounds on the seat. With 0.800" lift, I don't want valve float at 7500 rpm.
If your valve springs are weak, adding shims won't help since they'll probably create more problems. If your springs are weak, replace them.
Thread Starter
Member
iTrader: (1)
Joined: May 2010
Posts: 112
Likes: 2
From: Saskatchewan, canada
Car: 1982 Firebird T/A
Engine: 305
Re: Valve Spring Shims
They're used to get the proper spring install height. Adding shims to spring height that hasn't been checked may lead to coil bind since you're shortening the install height.
My spring pockets are deep and I have longer than stock valves to allow taller springs for more valve lift and spring rate. I use spring guides under the springs and shims under the guides to get the recommended install height for the springs I use. The triple springs for my BBC have around 800 pounds open pressure and around 300 pounds on the seat. With 0.800" lift, I don't want valve float at 7500 rpm.
If your valve springs are weak, adding shims won't help since they'll probably create more problems. If your springs are weak, replace them.
My spring pockets are deep and I have longer than stock valves to allow taller springs for more valve lift and spring rate. I use spring guides under the springs and shims under the guides to get the recommended install height for the springs I use. The triple springs for my BBC have around 800 pounds open pressure and around 300 pounds on the seat. With 0.800" lift, I don't want valve float at 7500 rpm.
If your valve springs are weak, adding shims won't help since they'll probably create more problems. If your springs are weak, replace them.
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