Conical valve springs.

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pamotorman
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Re: Conical valve springs.

Post by pamotorman »

there must be a good reason GM went to them on the LS engines as I am sure they cost more to make
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Re: Conical valve springs.

Post by Ron E »

They're used by a lot of OE's all over.
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Re: Conical valve springs.

Post by Zmechanic »

My hunch is that by making them conical, it causes a progressively changing natural resonance frequency throughout the entire coil. That would have the effect of lowering the Q, so the entire resonance band is wider, but it is more dampened. Maybe?
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Re: Conical valve springs.

Post by pamotorman »

I would guess it cuts down on harmonics while also reducing the weight of using a double spring or a inside flat wound damper
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Re: Conical valve springs.

Post by Truckedup »

Kibblewhite Beehive springs on the old British OHV bikes in racing retain their pressure longer than multiple springs .That's not a bad thing
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
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Re: Conical valve springs.

Post by groberts101 »

Truckedup wrote:Kibblewhite Beehive springs on the old British OHV bikes in racing retain their pressure longer than multiple springs .That's not a bad thing
yeah.. funny how Comp Cams takes all the credit for their design though I imagine they may have just generalized about the ovate wire and let people run with the rest of the story.

I think some are confusing the difference between beehive vs conical. They are somewhat different and the shape naming should be fairly evident. Good description of benefits and some comparison pictures located here.

http://www.hotrod.com/how-to/engine/140 ... arches-on/
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Re: Conical valve springs.

Post by MadBill »

The 1961 Buick 215" aluminum V-8 I (half) installed in a 1959 Bug Eye Sprite had conical/beehive springs. I think others in the mid-fifties did too. Wouldn't be surprised to find someone used them in the twenties, teens, etc...
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Re: Conical valve springs.

Post by Truckedup »

Beehive springs in a circa 1915 aircraft engine installed in a custom reto race car

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Re: Conical valve springs.

Post by MadBill »

"There's noting new under the Sun." :)
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Re: Conical valve springs.

Post by groberts101 »

Truckedup wrote:Beehive springs in a circa 1915 aircraft engine installed in a custom reto race car
That's an awesome looking ride wood frame and all. Plus, now I get to tell people that I try to build all my engines with airplane engine valvesprings in them! :D
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Re: Conical valve springs.

Post by andyf »

I'm in the process of setting up a big block Mopar with a set of Comp 7245-16 dual conical springs. So far so good. These spring require special locators and retainers and they want to be set up around 2.00 inches.

The interesting thing is that the book says they are 150 lbs at 2.00 installed height but when we measure them we get 205 lbs at 1.975. I'm guessing that Comp measures them with two flat surfaces 2.00 inches apart but in real life you have to use the stepped retainer and locator. The steps on both the locator and retainer compress the inner spring and add more load.

Anyway we ended up with 205 on the seat and 660 over the nose with 0.750 net lift. Should have the engine up and running on the dyno in a couple of weeks and we'll see how it does. I like these springs so far, hope they work as good as they should.
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Re: Conical valve springs.

Post by BigBlockMopar »

My uneducated brain tells me these springs (besides being able to handle a wider range of harmonics) could also allow a little more compression before coilbind happens, as the coils don't stack-up right on top of each other but just slightly off. Double win of GabbleBab.
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Re: Conical valve springs.

Post by Alkyfool »

Is there any thought that you can run lower seat pressure with conicals? I saw the 150# installed seat pressure also and thought they would never be used with a solid roller. I could see the smaller retainer weight and harmonic and spring surge control benefits.
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Re: Conical valve springs.

Post by hoffman900 »

Alkyfool wrote: Sat Jan 13, 2018 8:36 am Is there any thought that you can run lower seat pressure with conicals? I saw the 150# installed seat pressure also and thought they would never be used with a solid roller. I could see the smaller retainer weight and harmonic and spring surge control benefits.
You absolutely can run that seat pressure on a solid roller. NASCAR does it all the time. Others who develop valvetrains on Spintrons can get them there as well.
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Re: Conical valve springs.

Post by Firedome8 »

Old cb 350 Honda's had conicals and a 10K rpm red line.
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