53 willys

So whats the word?? I hear good and bad....

some good...If one spring breaks the valve can not fall onto the piston?
A single spring is not capable of having progressive loading and a tall enough coilbind?
Some bad...
Titanium keepers get thin and break??
dual springs bind sooner??
I don't know enough about them either way....
so tell me WHY!! a dual or single Valve spring is better????
Thanks for the Schooling...

mopardamo

Hello,

Not sure I can school anyone but I have some info. The Beehive spring is used to reduce harmonics in the valve train primarily. It is not a stronger spring. They use better metal supposedly to allow the reduced weight/coil diameter. A smaller retainer is part of the reduced weight and better harmonic control. I know little to nothing about diesel springs. My info comes from gas drag cars. There was not a beehive spring even close to being able to control my cam. With the low rpm and extremely light spring pressures of a diesel I cannot see a benefit to the design. I also cannot see a negative. Ti retainers are fine for high rpm motors and diesels ain't that! Dual spring do not bind sooner. It is a function of the design. The practicality may be true due to parts availability though. At the low rpm of a diesel, with my limited knowledge, I do not see an advantage with a dual spring. In gassers modern dual springs are needed over .550 lift in general.

Damon

mopardamo

Hello,

Not sure I can school anyone but I have some info. The Beehive spring is used to reduce harmonics in the valve train primarily. It is not a stronger spring. They use better metal supposedly to allow the reduced weight/coil diameter. A smaller retainer is part of the reduced weight and better harmonic control. I know little to nothing about diesel springs. My info comes from gas drag cars. There was not a beehive spring even close to being able to control my cam. With the low rpm and extremely light spring pressures of a diesel I cannot see a benefit to the design. I also cannot see a negative. Ti retainers are fine for high rpm motors and diesels ain't that! Dual spring do not bind sooner. It is a function of the design. The practicality may be true due to parts availability though. At the low rpm of a diesel, with my limited knowledge, I do not see an advantage with a dual spring. In gassers modern dual springs are needed over .550 lift in general.

A molly retainer and a beehive spring would seem to be a combo for a diesel but probably overkill for 95% or greater of the performance uses. Then again I do not know diesels enough. Yet!

Damon

53 willys

the more I read the less appealing the dual springs sound....I am REALLY worried about the TI retainers longevity.....they dont seem to be built to last they seem more like a way for weight reduction..but if it is at the cost of reliability then I dont want them...I wanna put springs in and FORGET about them!!! I dont want busted TI retainers after 30k miles.....

jrussell

Sounds like F1 springs would be the way to go.

Kman9090

Who uses the dual spring design?

Don M

The Cummins is a durable engine. Most parts/pieces have at least 100% protection built into the design. We know the rods and crank are stout. The block is as well. The valvetrain is nice for the designed purpose too.

Anything that reduces that durability is a step backward in the whole idea of having an engine made to last a long time. Titanium is not for long term use as a retainer, connecting rod or any part stressed this high. Linmited super high performance, track only, etc one could use Ti and get away with it. Driving across the country towing a camper would be an example of where not to use Ti.

The good news is; at 4000 RPM Ti is NOT needed. The factory steel retainers are perfectly fine with a good spring. The Cummins is not a Chevy, Honda or similar gasser that revs to 7500 RPM and up.

XLR8R

That's right Damon - valve spring dampers are primarily for higher-revving gassers... my '65 GTO has triple valvesprings, the inner of which is a flat-wound damper.
Like Don said, what's the benefit to using Ti retainers on anything less than 5K?

The CTD's designed RPM operating range really makes it's durability/overload engineering apparent far beyond what's visible in terms of physical size.... what's that old saw about how a reciprocating assembly's inertial loading increases as the square of it's RPM? (sic)

soulezoo

Part of why 455's and Caddi 500's never really made good racing engines (or at least not as good as others like the mopar 440)-- too much rotating mass... but it doesn't mean that it wasn't well tried.

soulezoo

One thing I'll add... and I will qualify this as only second hand info as I am not an engineer or engine pro... (and I don't want to get into the whole blown up affair that went on at a different forum/same subject... this is a nice place) is that dual springs also help to cancel out the harmonics each produces. I would agree (my own opinion here) that stock retainers or even chromoly retainers are plenty fine enough for our valve train and Ti is not needed. However, being an aircraft mechanic and working with Ti daily in critical high stress, high wear, high temp -- high everything you can think of applications where critical and necessary, Ti is the metal of choice. And while I have seen the pics/threads of the Ti retainer failure, I think it is about as wide spread a deal (and equally overblown, no pun intended) as the CFM+ manifolds blowing up everywhere... I think the whole idea of Ti being inferior, or even dangerous, in this application is simply ludicrous and an idea much too overblown from singular incidences where we really don't know all the other surrounding and underlying facts. Well known brand name turbos blow up here all the time... so we should stop using them too??
No, Ti is perfectly safe and well suited to this application. The real question is whether it is actually needed? That answer is obviously no.

WICKEDDIESELS

The addage of cancelled harmonics and if one spring breaks, the other will hold the valve in position, is a sales pitch. If a single spring (less mass) is correctly designed for the application. Properly featured with enhancements to increase cycle life and strength, will offer all you will ever need. There is no benefit from the weight savings, that the titanium retainer affords (in our application). Most just like the way the name Titanium sounds, and also the fact that it is a newer and somewhat exotic material. My background is in racing engines. I can assure that valve springs will move around on a Ti retainer, causing wear. In some cases, to the point of not being able to properly locate the spring. This reduces valve and valve guide life, as the spring will cause side loading to the stem and guide. I have rarely if ever seen such wear present in a "steel" retainer. With dual springs they will begin to rub against each other, causing wear. Bad part is, all that foreign material ends up in the oiling system. Might as well dump a table spoon full of metal shavings in with the oil. This is my opinion, not to discredit or promote anyones products.

Hintz

Who makes dual springs for the cummins? All I see are Don's, Wicked's, Hamilton's, and Pier's (even though I think Piers are Hamiltons) and they are all single spring.

53 willys

Greg Hoge(sp?) has some dual springs..all the other guys use single beehives...

WICKEDDIESELS

Hamilton, uses a beehive. Only one on the market for the Cummins I believe. I am pretty sure the dual springs are from a ricer application.

Don M

F1 Pro/sport springs are not beehive either. We use a straight spring that distributes the load across the retainer very evenly.

As an FYI; we have a new part that began shipping 3 weeks ago. Some dealers already have it on the shelf. It replaces the original part. It features slightly higher pressure curves and improved surface finish/refinement. It is a different color as well. This helps to indentify it against the older part/piece.

For the purpose of adding longevity and higher breakage resistance we still do some additional in-house, heat treatment on these parts just like in the past.