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Magnum valve spring question

Posted By: 1BAD68

Magnum valve spring question - 08/30/12 02:33 PM

I have a set of 318 magnum heads to install on my LA 318, got everything set to go but not sure about the springs.
Current cam is a Comp Cams .440 lift. According to what I've read, that will change to .469 with the magnums 1.6 rockers.
Will the stock magnum valve springs work with this? I can't find specs for those springs.
Posted By: dogdays

Re: Magnum valve spring question - 08/30/12 05:05 PM

Patrick, where are you?

Comp 901s will work.

R.
Posted By: 65rbdodge

Re: Magnum valve spring question - 08/30/12 06:00 PM

Quote:

Patrick, where are you?

Comp 901s will work if you machine the head so they fit.

R.



fixed

more info on this here-

http://www.bigblockranger.com/Magnum.html
Posted By: 70Cuda383

Re: Magnum valve spring question - 08/30/12 06:07 PM

No. they will not work


stock springs are barely enough for a stock cam. I can take them and compress them a little bit by hand, that's how weak they are.

they'll PROBABLY accept the lift though, as they don't run into clearance issues until .500 lift, but again, you'll float the valves long before you hit 5,000 rpm.

I would consider running the Hughes 1110 springs or something similar. that's a good all-around spring that works for a lot of cams.
Posted By: goldmember

Re: Magnum valve spring question - 08/30/12 06:12 PM

Several sources for a drop in valve spring,Hughes,MP,Bullet cams. 1.437OD is all that will fit without cutting the spring seats. Hughes has the springs and retainers that will work.
Posted By: 65rbdodge

Re: Magnum valve spring question - 08/30/12 07:47 PM

if you are really cheap like me you could get some springs/retainers from a GM 3.1 or 3.4 motor in the junkyard. with the lift you have, they will probably be at their limit. here they are on my heads, the 4 closest in the pic are the stock magnum springs, the other 4 are from a 3.4 motor. the redrilling jig i made on the other head too.

Posted By: GO_Fish

Re: Magnum valve spring question - 08/31/12 03:08 AM

stock Mag springs = Wimpy! Made for low RPM truck torque output, not high RPM horsepower.
Posted By: 1BAD68

Re: Magnum valve spring question - 08/31/12 01:45 PM

So these will work?... http://www.jegs.com/i/Comp-Cams/249/901-16/10002/-1

I assume I'll need retainers too?
Posted By: patrick

Re: Magnum valve spring question - 08/31/12 02:25 PM

Quote:

Patrick, where are you?

Comp 901s will work.

R.



https://board.moparts.org/ubbthreads/show...rue#Post3134434

ask and ye shall receive.

comp 901's have a ~1.1" coil bind height. you'll get about 1.6-1.64" install height with the proper retainers, so if you want to leave .060 before coil bind, that'll leave you with .440-.480" max lift, depending on install height.

for this moderate lift, I'd use either the GM3100 springs and retainers, or for about the same price, hughes #1110 springs and either used 2.2L retainers or hughes retainers. that'll give you ~.040-.060" more lift capacity than the the GM3100 springs, for about the same price (if you're not junkyard scrounging)

Posted By: 1BAD68

Re: Magnum valve spring question - 08/31/12 02:54 PM

Is any machining needed to make the Hughes 1110 springs fit? I noticed they have dampers.
Posted By: patrick

Re: Magnum valve spring question - 08/31/12 05:06 PM

nope, they dropped right on my magnum heads.
Posted By: dogdays

Re: Magnum valve spring question - 09/03/12 06:06 PM

Anyone have a retainer for the beehive springs and 3/8" stems?

Thanks,
R.
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