Spring adjusters question

[bgwolfpack]

Has anyone considered adapting something like these to the bottom of the front stock coils (especially you big bumper boys)

Does the spring rate compound in compression? If so, on the bottom in the rear for weight distribution also?

Am I completely in left field with this? I'm not looking to raise vehicle height with this per-say, just increase spring rate of the stock coils.

Disregard springs in pic. ? is about adjusters only.

[Trail X]

You're going to make me pull out the old physics lesson aren't you...

This is something many people don't understand at first, but the only way to stiffen a spring is to adjust it's coil properties... that would require a new spring to be swapped out.

By screwing or unscrewing the adjuster, you would only be raising or lowering your vehicle. Some people "say" they feel a stiffer ride due to a lift. This is physically impossible from a spacer lift... what they are feeling is a physical phenomenon with the suspension geometry, where the body rolls less with the lifted geometry due to a higher virtual roll center. The other element to feeling a stiffer ride is upgraded shocks, but they don't provide extra support for a heavy front end.

The misconception comes when people feel like they are compressing the spring more to fit the extra spacer in. Yes, the spring is compressed more in the unweighted strut... but as soon as you add weight, the spring will be exactly the same height.

Here's an old picture I used to explain how the BDS didn't affect the spring's compressed height when under weight.



Spring rate for these springs is linear. The unit for the spring constant is force/displacement. So displace it 1 inch, and it produces, say, 300 lbs of force; displace it 2 inches, and it will produce 600 lbs of force. However, in a vehicle situation, it's almost working in reverse because the vehicle and spring are at equilibrium. Vehicle's weight = force on spring. So if you work backwards, you can determine how far the spring will displace when under said vehicle's weight.

If you want a stiffer ride to compensate for a heavier bumper, see the factory springs thread: viewtopic.php?f=15&t=158 For now its the only way to get a stiffer spring/ride.

Although, your idea could theoretically produce lift if adapted properly. It would just be adjustable lift. A similar thing is possible if you just chuck your shock in a lathe and cut another clip recess into the housing for the lower spring perch.

Here's to thinking!

[bgwolfpack]

Thank you sir. I do understand the point your making. So with that in mind let me continues the blasphemous questions.

How about a continuous and permanent spring rubber?

I realize the rears can be helped with air, can the fronts as well? I personally don't like the air systems, they seem cheap and prone to problems.(That statement should bring the ire up of a certain someone)

[Philberto]

Hey! Although James is correct that a spacer won't stiffen a spring, no matter how adjustable, a spacer that is fixed so as to adjust preload of the spring can generate a stiffer ride (this is utilized on many motorcycle suspensions as a cheap alternative to adjustable shocks). The only modification would be to replace the lower spring mount on the front strut with something accepting a spacer that has an adjustable component... If you can generate constant compression on a progressive rate spring, then the initial spring rate will be higher than the rate on a stock-compressed (no more compression than the weight of the vehicle) spring. At least in theory, that'll work... just my 2 cents. Wanna chime in on this James? I believe that spacers can generate a stiffer ride if they preload the spring even at full extension of the strut. The only problem with this as far as I can see is that you may be shortening the shock life due to the higher spring force on the shock at all points of suspension travel.

[The Roadie]

I even went to far as to buy some threaded collars meant for rear springs, and try to adapt them for the front. Until I understood what JD was saying. It's possible, but the big benefit will be the Icon coilovers we're getting soon. Then the shock is also upgraded to handle the heavier weight, and the unit is built to accept standard size springs so we can specify they get built with 450, 500, 550, 650 pound-in springs from a stock catalog. Fine tune the springs - fine tune the shock - enjoy!

It should be possible to design new upper and lower perches to use catalog springs with the existing shocks, but that's a bunch of work with 3D to get the ramp angles just right.

[bgwolfpack]

I even went to far as to buy some threaded collars meant for rear springs, and try to adapt them for the front. Until I understood what JD was saying. It's possible, but the big benefit will be the Icon coilovers we're getting soon. Then the shock is also upgraded to handle the heavier weight, and the unit is built to accept standard size springs so we can specify they get built with 450, 500, 550, 650 pound-in springs from a stock catalog. Fine tune the springs - fine tune the shock - enjoy!

It should be possible to design new upper and lower perches to use catalog springs with the existing shocks, but that's a bunch of work with 3D to get the ramp angles just right.

I know the Icon coilovers will fix most all issues. I realize though it will be quite awhile until I can afford such a nice peace. Every time Icon comes up I want to drive over and see what their doing on our new coils.

[Trail X]

Hey! Although James is correct that a spacer won't stiffen a spring, no matter how adjustable, a spacer that is fixed so as to adjust preload of the spring can generate a stiffer ride (this is utilized on many motorcycle suspensions as a cheap alternative to adjustable shocks). The only modification would be to replace the lower spring mount on the front strut with something accepting a spacer that has an adjustable component... If you can generate constant compression on a progressive rate spring, then the initial spring rate will be higher than the rate on a stock-compressed (no more compression than the weight of the vehicle) spring. At least in theory, that'll work... just my 2 cents. Wanna chime in on this James? I believe that spacers can generate a stiffer ride if they preload the spring even at full extension of the strut. The only problem with this as far as I can see is that you may be shortening the shock life due to the higher spring force on the shock at all points of suspension travel.

Stiffness is related to the spring constant, right? Spring constant is not affected by adding an external spacer of any sort. Changing out the spring for a spring with a higher spring constant is the only way to obtain a 'stiffer' ride due to a spring change. Most of us change out our shocks at the same time we add a spacer... a new shock can help produce a stiffer feeling.

Some GOOD reading on this topic: http://www.sportrider.com/tech/146_9510_tech/index.html

The problem with stiffer springs, roadie, is that they would actually limit your articulation more. Think, if you're in a situation where you're only on two wheels right now, and it's deflecting the spring 3", a stiffer spring may only deflect 2"... thus keeping your weightless wheels 1" further off the ground that before. What you theoretically want is a longer spring with a lower spring rate... that would contribute to better articulation... however it's harder to tune in your correct rest height if you have varying payloads. Combine the longer, softer spring with a heavy duty shock, and you should be pretty golden (but this also means that the vehicle may oscillate at a higher amplitude after a bump, which could mean more slider/frame hitting after coming off a rock). Seems everything is a trade-off eh?