Dual valve spring inner spring question
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Dual valve spring inner spring question
Amazon package came today and noticed that the inner spring on 660 dual springs come apart very easily on some of the springs. Some are very tight and can't pull apart and others just slide out. Some just come apart from lifting the spring off the table. Is this normal? Previous springs I've seen have never come apart so easily. I know they can come apart, but why the differences?
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Amazon package came today and noticed that the inner spring on 660 dual springs come apart very easily on some of the springs. Some are very tight and can't pull apart and others just slide out. Some just come apart from lifting the spring off the table. Is this normal? Previous springs I've seen have never come apart so easily. I know they can come apart, but why the differences?
Drifting
Joined: Mar 2000
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From: Maryland
I've been using a spring that is supposed to be high quality (AFR-8019, PAC-Premium, racing) and the interference fit between them is also not consistent (but maybe not as bad as yours sound).
I am curious as to exactly which BTR springs they are (what's the spec for seat and open pressure). Also very curious about the perpendicularity on the end grind. If you separate a few of the springs, stand them on end (on a flat surface), and hold a square next to them, do they appear to be standing up straight or are the tilted (how bad)? Flip end to end and check the other side.
I'm going to pull mine and check the pressures next month. If they're done, I've been thinking about trying the BTR Max Pressure spring which has similar (slightly lower) pressures than the 8019.
Thanks
Rob
I am curious as to exactly which BTR springs they are (what's the spec for seat and open pressure). Also very curious about the perpendicularity on the end grind. If you separate a few of the springs, stand them on end (on a flat surface), and hold a square next to them, do they appear to be standing up straight or are the tilted (how bad)? Flip end to end and check the other side.
I'm going to pull mine and check the pressures next month. If they're done, I've been thinking about trying the BTR Max Pressure spring which has similar (slightly lower) pressures than the 8019.
Thanks
Rob
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I can tell you that the PAC 1905 springs I ran for 50,000 miles (with a .600" lift cam-higher lift will require more frequent spring changes) all had an interference fit between inner and outer. All 16 springs also had the same feel as far as interference/drag was concerned. The interference is there to help dampen spring bounce. If you don't have the interference, that would reduce the rebound/spring/damping protection for that spring. Maybe it is just me, but I always buy my springs from the spring manufacturer, sometimes thru a second party like Jegs or Summit. But they are advertised at the retailer as brand name springs, i.e. PAC, PSI, etc. When you buy from a speed shop, who knows who made the springs. My .02......
Last edited by grinder11; Dec 14, 2024 at 09:25 AM.
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