408 hyd roller, too much spring pressure?

Phreakish

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Not necessarily. Mass absorbs energy but it also releases it in the form of heat. The transfer of energy from one mass to another (ie: steel spring to air/oil) is a function of surface area.

Valve springs absorb kinetic energy (movement of mass) and store that energy until it is released. However – as you rightly pointed out that there is no such thing as a free lunch – some of that kinetic energy is converted into thermal energy, which is released by the spring mass when it comes into contact with oil and air (conductive and convective heat), and to a lesser extent the other metal surfaces it is in contact with (valve seat, valve stem/retainer etc).

A spring with a smaller mass but a larger surface area (an ovate shaped spring, for example) is able to absorb more energy because it is able to transfer excess energy at a faster rate. The more energy a spring can release in a given amount of time, the more total energy it can absorb in that same amount of time.

Distribution of mass determines rate of energy transfer.

Greater surface area = faster heat transfer = less stored energy.

In addition, lower spring rate = less pressure = less heat = less energy transfer to begin with (they are all the same thing).

Finally, what came first: the chicken or the egg?

A beehive or conical spring, by design, is always going to have a smaller retainer. Suggesting that a beehive needs a smaller retainer (less weight) to control the valve-train is an oxymoron: if the spring didn't have a smaller retainer in the first place, it would not be a beehive.

Doesn't work that way. Less mass will literally lower thr loads or the amount of compression (lift).
Ive designed hundreds of springs in the past couple decades, and unless you go to some super exotic material this is exactly how it works.
Ovate wire can allow beehive geometry through without a loss of cross section.
 

MOPAROFFICIAL

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I have paw doubles that match those specs within a 'c hair' on some 974 heads with a .520 hyd roller.
To each his own, stop jerking on this dead horses dingus already.
 

Phreakish

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If a greater mass stores more kinetic energy, then at some point it needs to release that greater energy. Sometimes that greater energy is released at an inopportune time, such as when the valve has already closed. This relates to harmonics, or oscillation of the two massed springs.

View attachment 1715979472

That graph basically only shows a difference in spring rate, because conical are non linear. The resonance is still the same, and the loads will be more difficult to hit.

In a perfect work, a conical or beehive would have a wire diameter that varies with the od of the coil, that's the only way to keep the stress along the wire the same.
Again, spring engineering is hundreds of years old. Literally nothing new under the sun. There are calculators for all this.
 

Ted265

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They should, afterall, they are China slave, sweatshop heads..
Yes they are chinese heads, thats why I bought the bare castings not the assembled heads. I've used the Edelbrock heads in the past - mediocre valve job, stem heights were all over the place and the castings were pretty rough in comparison. So once you add the cost of a good valve job the price difference becomes fairly substantial. By then you might as well spend the bit extra for a set of Trickflow heads - which would be wasted on a mild 318.
 
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