Author Topic: Beehive valve springs (Read 968 times)

monkeystash · « **on:** November, 26, 2008, 08:18:02 AM »

I was doing some in depth research to see if the hype was all true....and I think it is. By changing to beehive springs and smaller retainers, you can cut valve train weight in half. One dyno test, link below, showed a gain of 65HP at 6000rpms on a hydraulic roller engine after the heavy traditional springs fell off at 5700rpms. WOW! AFR now uses 8mm valves instead of the typical 11/32 valves to also reduce weight, however they don't come with beehives standard. While the majority of people don't spin over 5500rpms, for those who do, this is a cheap way to add some HP. In fact, it is a no-brainer! The beehives cost twice what the standard springs do, about $200 for the springs. I'm currently building a 302 for my Fairlane with RHS180 heads and am going to try out these beehive springs first hand.

http://www.popularhotrodding.com/tech/0607phr_camshaft_basics/photo_32.html

http://www.fordmuscle.com/archives/2007/08/SpringTime/index.php

Starfury · « **Reply #1 on:** November, 26, 2008, 10:45:18 AM »

I haven't read the articles, but you do realize that that 65hp is more from added rpm than weight reduction in the springs? The problem with the 'benchmark' springs is that they were floating at 5700. Adding springs strong enough not to float allowed the engine to wind to 6k, increasing max hp.

I'm good with my Comp Cams double springs. They definitely don't float at 6200, where my cam dies off.

napaguy · « **Reply #2 on:** November, 26, 2008, 01:53:33 PM »

You two have to be the geekest engine guru's ever... :dance

monkeystash · « **Reply #3 on:** November, 26, 2008, 07:26:39 PM »

Quote from: Starfury on November, 26, 2008, 10:45:18 AM

I haven't read the articles, but you do realize that that 65hp is more from added rpm than weight reduction in the springs? The problem with the 'benchmark' springs is that they were floating at 5700. Adding springs strong enough not to float allowed the engine to wind to 6k, increasing max hp.

I'm good with my Comp Cams double springs. They definitely don't float at 6200, where my cam dies off.

Ahhh, I'm glad you said that, because that is what page 2 of the Ford Muscle article says most people will say. They call it "erroneous thinking."

"These seemingly small weight savings mean a lot in terms of power. Every gram of reduction in the moving valvetrain components frees up some 35 rpm. (Obviously the gram needs to be removed across all eight pairs of valves.) When you consider that a twenty-gram savings is on the low end of what can be achieved by just changing the spring set, you quickly see that an engine can spin another 700 rpm beyond its current redline. Some are quick to dismiss this as a mere extension at the end of an engines power curve. This is erroneous thinking. The majority of dyno sheets that show power flattening out or diving after peak power is made are not showing that the "cam is done", or "the heads are choking", but rather that the engine is likely experiencing the limitation of its valve springs."

Funny thing is, this comparison was done using Comp Cams double springs vs beehives. And yes I do realize the extra ponies are from the extra rpm, but the extra HP is still not obtainable with traditional springs, regardless of their stiffness. The beehive springs are in fact less stiff, so it doesn't matter if you have triple springs on Viagra.

Here is a bit more tech on them:

"The resultant design is a valve spring that is conical shaped (or Beehive shape as Comp's trademark reflects.) This design makes sense from a variety of standpoints. First, valvesprings unlike other types of spring uses, compress from the top down. The bottom coils, in fact, often don't compress at all. Therefore if the increase in pressure is created by the top most coils, while the bottom remain at a relatively lower rate, you end up with a spring that serves its valve control purpose, but also "dampens" the shock from the closing valve. This variable rate design also helps eliminate valvetrain harmonics - resonance frequencies that damage metals and lead to loss of control.

The benefits of conical springs doesn't end there. It turns out the design lends itself to a reduction in spring weight through three factors. First, the smaller coils up top means less material AND a smaller diameter retainer - weight saved. Second, the smaller coils and variation in coil spacing, yields spring rates that otherwise must be achieved through increased wire size - weight saved again. Finally, the harmonic dampening properties of a progressive rate spring and tapered wire allow eliminating the need for an inner second spring and damper - even more weight saved."

How 'bout them apples!

Starfury · « **Reply #4 on:** November, 27, 2008, 12:20:16 AM »

While I won't argue that they're a good design and serve a purpose in certain ircumstances, I think a lot of that info is hype. I'm sure the manufacturer of said beehive springs contributes to both of those sites.

Lightening the valvetrain components does help improve power, but it's not going to magically increase the redline of an engine. The only reason valve springs would contribute to rpm limiting an engine would be if they float at high rpm's. If the cam dies off before the valve springs float, you don't really have an issue. A cam is only going to make power across a certain rpm band. Once you pass peak efficiency, all it's going to do is fall off as rpm increases. You might be able to broaden the power curve a hair by reducing valvetrain mass (which chews up power through inertia), but I don't buy that it's going to magically increase your useful powerband all that much.

monkeystash · « **Reply #5 on:** November, 27, 2008, 06:20:45 AM »

Whatever my friend. Believe what you want, but GM uses them on Gen III/IV engines as does Ford on some engines. In fact, the majority of OEMs are moving this direction too. Some OEMs were using them as far back as the mid 1990s (GM, Ford, BMW to list a few.) I think the "hype" can now be defined as proven technology.

ShadowLands · « **Reply #6 on:** December, 14, 2008, 08:40:16 PM »

Quote from: Starfury on November, 27, 2008, 12:20:16 AM

While I won't argue that they're a good design and serve a purpose in certain ircumstances, I think a lot of that info is hype. I'm sure the manufacturer of said beehive springs contributes to both of those sites.

Lightening the valvetrain components does help improve power, but it's not going to magically increase the redline of an engine. The only reason valve springs would contribute to rpm limiting an engine would be if they float at high rpm's. If the cam dies off before the valve springs float, you don't really have an issue. A cam is only going to make power across a certain rpm band. Once you pass peak efficiency, all it's going to do is fall off as rpm increases. You might be able to broaden the power curve a hair by reducing valvetrain mass (which chews up power through inertia), but I don't buy that it's going to magically increase your useful powerband all that much.

Actually....Comp wasn't the first to manufacture a beehive spring. Beyond the weight savings of the tapered spring design is the ability of this design to dampen valvetrain harmonics which further enhances high rpm stability. With less harmonics the valve stem is not transmitting vibration to the valve guides through "wobble". Further down, the valve seat is more securely sealed since the head of the valve is not bouncing around on it's seat. These factors all contribute to added horsepower...not just weight savings. These factors will increase the useable rpm range of most camshafts. Beyond that....there is simply a more efficient engine at work which will produce more horsepower.

Having stated that....if you are happy with your double springs....great! Just don't off-handedly dismiss the technology because you believe a certain manufacturer has a great PR department.

Starfury · « **Reply #7 on:** December, 20, 2008, 01:16:18 PM »

Nothing to do with PR, just that I won't instantly accept something as far superior just because it was published in a performance magazine. It's well known that many of those publications are funded by manufacturers, and that they'll publish articles supporting said manufacturers.

They've been around and I'm sure they work, but I'd bet all of those numbers are inflated.

huskinhano · « **Reply #8 on:** January, 13, 2009, 06:35:14 PM »

There was a discussion about behives by Dave Freiburger of Carcraft & Hot Rod mag fame on www.freiburgersjunkyard.com He had noticed that the behives don't seem to hold up to well on more radical profiles. A couple of engine builders jumped in and said the same. Do a search there.

68EFIvert · « **Reply #9 on:** January, 13, 2009, 10:27:50 PM »

Quote from: huskinhano on January, 13, 2009, 06:35:14 PM

There was a discussion about behives by Dave Freiburger of Carcraft & Hot Rod mag fame on www.freiburgersjunkyard.com He had noticed that the behives don't seem to hold up to well on more radical profiles. A couple of engine builders jumped in and said the same. Do a search there.

I have heard some of the same reliability issues but don't have any experience with them myself.

monkeystash · « **Reply #10 on:** January, 14, 2009, 07:30:09 AM »

Quote from: huskinhano on January, 13, 2009, 06:35:14 PM

There was a discussion about behives by Dave Freiburger of Carcraft & Hot Rod mag fame on www.freiburgersjunkyard.com He had noticed that the behives don't seem to hold up to well on more radical profiles. A couple of engine builders jumped in and said the same. Do a search there.

I did a search and found nothing. Could you please link me to comments you speak of. Thanks.