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Any disadvantage to "over-springing"?

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Old Feb 22, 2005 | 08:17 PM
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Default Any disadvantage to "over-springing"?

I got a baby cam (221/221 .558/.558 114) which might
or might not be able to work OK with Z06 springs and
Z06 valves (already in hand). I just got a set of Crane
dual springs (832) with titanium retainers which are
the other side of overkill I think. Today's question is,
is there any downside to using a spring that's "too
good"? Given that it's already paid for etc., what if
any downside is there to using a higher lift capable,
maybe (?) higher seat pressure spring? Would there be
any reason not to use the 832s? I'd think that, being
not taken close to their lift limit should give them a
decent life expectancy?
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Old Feb 22, 2005 | 08:20 PM
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Only thing I can think of is a higher chance of a collapsed lifter??
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Old Feb 22, 2005 | 08:21 PM
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crane duals ideal for this application
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Old Feb 22, 2005 | 09:06 PM
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the cranes only have 115#'s @ 1.800, open is 352 though i dont know at what height. i agree with the above guy, they will work great with your cam. or you coud always go with the venerable 918's.
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Old Feb 22, 2005 | 09:07 PM
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the crane/ vinci duals can be set for whatever spring pressure the cam requires. here's specs for the springs.

VHP DUAL VALVE SPRING KIT
112lbs @ 1.800
352lbs @ 1.150
will handle .650 lift with .045 coil clearance

i've been using them on the wife's car for almost a year now on the stock cam. no issues whatsoever. one thing about 'over-springing' is that it's good to go high at first. due to heat cycling and normal wear and tear, you lose spring pressure. so, say, your cam needs 100# seat pressure. i'd go 110# installed. ater heat cycling and usage, it'll come down.

Last edited by mrr23; Feb 22, 2005 at 09:12 PM.
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Old Feb 22, 2005 | 09:20 PM
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The only real disadvantage in using springs more stout than you need is the horsepower robbing parisitic loss due to the cam having to push harder to open the valves. remember the only job a valve spring has to do is keep the lifter in contact with the cam lobe. The spring has to have enough pressure to slam the valve shut before the lobe comes back around again.
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Old Feb 22, 2005 | 09:23 PM
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yes, i agree, TOO much can be bad. i wouldn't put a spring with say 30 lbs more than needed. you can wipe a cam lobe or ruin a roller on the lifter.
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Old Feb 23, 2005 | 12:16 AM
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i was worried about this over-springing idea as well. i think i may have a collapsed lifter (noise now, pushrods/rockers look good). when i pull the heads to replace (with comp r's i think), i want to replace the valve springs as well (mucho easy w/ heads off). i want to be able to run my stock cam (probably into this summer), but have a damn fine valvetrain already in place for when i get the money to get a 230+ cam like i want and a good tune.

the ppc gold kit w/ dual springs/Ti retainers/seats/seals is looking MIGHTY fine to me! will this be kosher if i am running stock cam/new lifters? i'm always for doing somthing once with good stuff, i dont like learning from mistakes if i dont have to

sorry for my semi-hijacking!
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Old Feb 23, 2005 | 08:05 AM
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Right now, I'm running too much spring. I have a GT2-3 cam that LPE specs to use the stock LS6 springs, but I'm running the duals that came on my AFR heads. The LS6s have 90lb. seat pressure, the AFRs are 130lb. (measured by me). The car is running good, and the valvetrain is somewhat quiet, but I know that the springs are costing me power, that they'll wear out sooner because of the more brittle material, that I'm getting more pushrod deflection than I need to, that the guides and seats are wearing faster than they have to, and that the lifters will die sooner.

Next, I'll probably try a set of Comp 915 springs with titanium retainers. They're around 110 on the seat, perfect for my cam. The 918s are over 130, overkill for a mild cam IMO. I gotta get beehive springs back on this car, it looks like a dinosaur with those old design duals on it!

Last edited by Flareside; Apr 29, 2005 at 10:22 AM.
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Old Feb 23, 2005 | 12:58 PM
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as long as the spring isnt stiffer than the stiffest spring one would use on the most radical hyd roller cam someone would use...the only downfall is gonna be loss of power (not sure if that makes sense ). probably not enough to notice...but if ur trying to get every last ounce of power...then its critical.

not saying this spring is too stiff for you (to where it would rob power)...just saying that "if" if was too stiff youd be leaving power on the table.
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Old Feb 23, 2005 | 01:30 PM
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Originally Posted by Flareside
Right now, I'm running too much spring. I have a GT2-3 cam that LPE specs to use the stock LS6 springs, but I'm running the duals that came on my AFR heads. The LS6s have 90lb. seat pressure, the AFRs are 130lb. (measured by me). The car is running good, and the valvetrain is very quiet, but I know that the springs are costing me power, that they'll wear out sooner because of the more brittle material, that I'm getting more pushrod deflection than I need to, that the guides and seats are wearing faster than they have to, and that the lifters will die sooner. Because of all those factors, I'm going to swap out the springs pretty soon. I installed them as an experiment, I wanted to see how much of a different dual springs make in regard to valvetrain noise. The good news is that the springs don't seem to be a noise factor at all, they sounds stock.

Next, I'll probably try a set of Comp 915 springs with titanium retainers. They're around 110 on the seat, perfect for my cam. The 918s are over 130, overkill for a mild cam IMO. I gotta get beehive springs back on this car, it looks like a dinosaur with those old design duals on it!
might want to look into the manley nextek

Max Valve Lift : .600"
O.D. : 1.255"
I.D. : .830
Installed Pressure : 115@1.750"
Open Pressure : 350@1.175"
Coil Bind : 1.100"

180$ w/ tit. retainers from SDPC
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Old Feb 23, 2005 | 01:51 PM
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Here's a related question for you guys:

When I was doing my cam swap, a friend of mine came over (he has plenty of experience with SBC/BBC's but not as much with LSX's). He told me running the springs I had (PRC duals) might put a lot of stress on my rockers (stock), and I should really consider upgrading to stud-mounted rocker arms. He says it happens with SBC's every now and then (not frequently, but it does happen). What are your thoughts? I know studs would be stronger, but are my rocker arm bolts being put under too much stress right now? Just curious, because his argument did make sense. If so, I guess that would be another drawback of running too much valvespring.
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Old Feb 23, 2005 | 02:22 PM
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If the stock lifters don't collapse with the PP gold's and a "big" cam, then why would they collapse with a medium or small cam? That doesn't make sense.
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Old Feb 23, 2005 | 03:08 PM
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Originally Posted by technical
If the stock lifters don't collapse with the PP gold's and a "big" cam, then why would they collapse with a medium or small cam? That doesn't make sense.
i guess thats the point i was trying to make
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Old Feb 23, 2005 | 03:16 PM
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ok, now I am confused. If I purchase the MS3 camshaft with low 600 lift, the PRC spring kit will be too much since its max is like 660?
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Old Feb 23, 2005 | 03:21 PM
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When the hell did .600" of lift become low?

I think you'd want a spring capable of .650" when you're already at .600"
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Old Feb 23, 2005 | 03:35 PM
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Quick thought. If the spring was just a bit stiffer than normal 15-20lb,
then even when worn it might be within spec of the cam. The HP/wear
cost when it is new might not be very high and it might make it worth
the while.
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Old Feb 23, 2005 | 05:25 PM
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kinda what i said. start off with a little more. that way as it wears, it'll lower itself to what you need anyway. but i wouldn't go above 10# more though.
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Old Feb 23, 2005 | 07:13 PM
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Originally Posted by Turo
Here's a related question for you guys:

When I was doing my cam swap, a friend of mine came over (he has plenty of experience with SBC/BBC's but not as much with LSX's). He told me running the springs I had (PRC duals) might put a lot of stress on my rockers (stock), and I should really consider upgrading to stud-mounted rocker arms. He says it happens with SBC's every now and then (not frequently, but it does happen). What are your thoughts? I know studs would be stronger, but are my rocker arm bolts being put under too much stress right now? Just curious, because his argument did make sense. If so, I guess that would be another drawback of running too much valvespring.
If you are worried about your rocker assembley I would sugest to go with pedistal mount rockers, not stud mount ones.
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Old Feb 23, 2005 | 09:51 PM
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Originally Posted by Texas_WS6
If you are worried about your rocker assembley I would sugest to go with pedistal mount rockers, not stud mount ones.
not really worried about it, since i havenlt read of any problems related to that. i was just asking for the sake of curiosity. im keeping my stock rockers for now
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