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These are new PAC 1215 springs, have maybe 20 miles so far. The #1 exhaust spring looks way off center. Is that normal? I don't recall seeing anything like that with my previous springs (stock, and LS6 springs). [edit: see #9 for another pic]
I just looked at the specs, it doesn't seem like are much better than oem blue springs. 294 lbs open at 1.200 height. Coil bind is at 1.140. Unless i looked up the wrong specs.
Rollers need a bit more spring than with a stock rocker, esp with an aftermarket cam.
I dunno, you could calculate the difference in spring pressure at max lift with whatever cam you're using vs the ls6 springs.
I just looked at the specs, it doesn't seem like are much better than oem blue springs. 294 lbs open at 1.200 height. Coil bind is at 1.140. Unless i looked up the wrong specs.
Rollers need a bit more spring, esp with an aftermarket cam.
True, but I had the blue springs before with those same rockers without problems, and wanted a little stronger and couldn't shim the blue springs since they were at the limit. Also this is purely a street car, didn't want to have to think about valve spring changes every 10K miles or whatever.
I think it's just how the coil looks at it "exits" the retainer. The rocker looks right over the stem. Not sure it's anything to sweat over...
Well the seat for the retainer isn't centered in the spring, so that must mean the spring isn't centered on the spring seat. Maybe that's not a big deal, I don't know. Seems like poor manufacturing to me. The blue springs I had before weren't like that, I sold them but have a pic:
Atleast take it apart and inspect it. Might just need re positioning or something
I wouldn't be running it like that, I know what happens when springs break!!! Great way to destroy your entire engine!
True, but I had the blue springs before with those same rockers without problems, and wanted a little stronger and couldn't shim the blue springs since they were at the limit. Also this is purely a street car, didn't want to have to think about valve spring changes every 10K miles or whatever.
Did you install the shims to increase seat pressure and have a tighter open height, or just to correct for install height?
What is your current height? We should be able to calculate what your current seat pressure actually is from that. What about cam specs? What spring pressures does your cam card call for? How close are you operating to coil bind? What height is the spring at full open?
Might want to contact comp or someone and see what they recommend for spring pressure to keep control the valve with their rockers.
I mean, with rollers, i would want to increase both seat and open pressure. You might get away with shimming, you might want better springs.
Last edited by dreadpirateroberts; 01-24-2020 at 04:26 PM.
Did the calcs, seat pressure is 114, open is 290, as shimmed. Agree I may want to go higher.
After removing the springs for #1, I found the one that looks off kilter when installed doesn't look different from the other other one when they're out. I did find .05-.06 play in the fit of the retainer where it sits in the spring, so that's my current theory for why it can end up off center. Retainers are stock (from 2000).
Did the calcs, seat pressure is 114, open is 290, as shimmed. Agree I may want to go higher.
After removing the springs for #1, I found the one that looks off kilter when installed doesn't look different from the other other one when they're out. I did find .05-.06 play in the fit of the retainer where it sits in the spring, so that's my current theory for why it can end up off center. Retainers are stock (from 2000).