Specs on the P5249847 Valve Spring

Posted By: cuda_tim

Specs on the P5249847 Valve Spring - 07/01/08 05:43 PM

Guys, I used P4120249 springs on my 340. They are rated for .430-500 lift. I took several of them off and had them tested at a machine shop, and as expected, they are pretty much shot.

A friend has a new set of P5249847's (for basically free), but I'm wondering if they would be much better. I can probably get them (he lives several states away) and have them tested, but I'm wondering if I should bother.

Furthermore, I can't seem to find much info on them, except that they do have a better lift .480-.535 at the same installed height. But, I'm concerned that they won't be a simple replacement for my old ones.

Anybody have any specs on these, like inside diameter of the outer spring?

Thanks!

Posted By: ZIPPY

Re: Specs on the P5249847 Valve Spring - 07/01/08 08:31 PM

Single with damper
OD 1.50
Wire Diameter .207
103lbs @ 1.67
260lbs @ 1.27
Install at 1.67 to 1.68

Nothing listed for ID, but figuring 1.50 - .414, just the spring should be in the neighborhood of 1.086. The damper shouldn't account for any more than .086 worth of real estate (probably less than that) so I think you're looking at something slightly over 1" for overall ID, with the damper figured in.

Posted By: cuda_tim

Re: Specs on the P5249847 Valve Spring - 07/02/08 04:06 PM

Quote:

Single with damper
OD 1.50
Wire Diameter .207
103lbs @ 1.67
260lbs @ 1.27
Install at 1.67 to 1.68

Nothing listed for ID, but figuring 1.50 - .414, just the spring should be in the neighborhood of 1.086. The damper shouldn't account for any more than .086 worth of real estate (probably less than that) so I think you're looking at something slightly over 1" for overall ID, with the damper figured in.

Thanks, Zip!

Is it possible you could also give me the specs on the P4120249 springs for comparison?

Thanks, Tim...

Posted By: ZIPPY

Re: Specs on the P5249847 Valve Spring - 07/02/08 07:15 PM

single wih damper
1.50od
.206 dia. wire
90 lbs @ 1.67
230lbs @ 1.27
install at 1.65 to 1.68

Posted By: RobX4406

Re: Specs on the P5249847 Valve Spring - 07/02/08 07:45 PM

No wonder the valves floated on your engine with those valve springs. Not even close to what's required.

Posted By: cuda_tim

Re: Specs on the P5249847 Valve Spring - 07/03/08 08:17 AM

Quote:

No wonder the valves floated on your engine with those valve springs. Not even close to what's required.

Yea, I'm surprized that they are considered "heavy Duty"...

At this point, I'm not even sure the P5249847's will do the trick. I'm using a VooDoo 60402 and it needs a whole lot better set of springs. The ones that Lunati recommends won't fit without machining. I don't really want to take the heads off, just for a set of springs. Especially since it is hard to find a machine shop that I can trust, that won't try to retire on my behalf.

I was thinking I might go with the BeeHives from COMP CAMS.

Anybody use those?

Thanks!

Posted By: RobX4406

Re: Specs on the P5249847 Valve Spring - 07/03/08 05:38 PM

Quote:

Quote:

No wonder the valves floated on your engine with those valve springs. Not even close to what's required.

Yea, I'm surprized that they are considered "heavy Duty"...

At this point, I'm not even sure the P5249847's will do the trick. I'm using a VooDoo 60402 and it needs a whole lot better set of springs. The ones that Lunati recommends won't fit without machining. I don't really want to take the heads off, just for a set of springs. Especially since it is hard to find a machine shop that I can trust, that won't try to retire on my behalf.

I was thinking I might go with the BeeHives from COMP CAMS.

Anybody use those?

Thanks!

I've used the 26120 comp beehives on a few engines. Good springs but expensive. They require a locater and not sure if that means machining the pad or guide boss.

I don't know who suggested using those MP springs with that cam, but, they didn't do you any favors.

I'd figure the cost to swap springs in total and go from there.

Good luck.

Posted By: scratchnfotraction

Re: Specs on the P5249847 Valve Spring - 07/03/08 07:37 PM

I used comp 901s on mine with a lunati voodoo roller cam 60710

did not float at 6200 rpm so far,noises over after 5500 but doing well

they where with in a few # of the lunati spring

they droped on with stock seals and retainers and stock roller gear

I have a set of the lunati double with damper for a paper weight now

,they use the same spring on all sb cams roller or flat tap