Conical valve springs.
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Re: Conical valve springs.
there must be a good reason GM went to them on the LS engines as I am sure they cost more to make
Re: Conical valve springs.
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.
I would guess it cuts down on harmonics while also reducing the weight of using a double spring or a inside flat wound damper
Re: Conical valve springs.
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.
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.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
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/
Re: Conical valve springs.
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...
Felix, qui potuit rerum cognscere causas.
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Happy is he who can discover the cause of things.
Re: Conical valve springs.
Beehive springs in a circa 1915 aircraft engine installed in a custom reto race car
Motorcycle land speed racing... wearing animal hides and clinging to vibrating oily machines propelled by fire
Re: Conical valve springs.
"There's noting new under the Sun."
Felix, qui potuit rerum cognscere causas.
Happy is he who can discover the cause of things.
Happy is he who can discover the cause of things.
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Re: Conical valve springs.
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!Truckedup wrote:Beehive springs in a circa 1915 aircraft engine installed in a custom reto race car
Re: Conical valve springs.
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.
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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Andy F.
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Re: Conical valve springs.
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.
Re: Conical valve springs.
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.
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.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.
-Bob
Re: Conical valve springs.
Old cb 350 Honda's had conicals and a 10K rpm red line.
A good test is worth a thousand opinions.
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