Front End Success ... sorta, need stabilizer advice

[boywonder]

Originally Posted by TomsBeast

Without getting to far off topic, a damper, or shock absorber, has a piston with a stack of washers and springs, and orifices that the oil passes through. As the suspension moves, that incompressible oil forces the spring washers, opens holes, and oil squirts through. That gives it the damping effect. The nitrogen gas isn't getting 'compressed' per se, it's under slight pressure and only in a nitrogen filled shock (which are kind of a modern thing), there to displace air bubbles from the oil. Void of nitrogen, the damper, shock, what have you, behaves just as a nitrogen one does, oil through orifices, but cavitation can induce air bubbles that get past the seals, under hard use. When that happens, those tiny bubbles act as a spring, within the oil fluid, and make you damper not perform all that well.

Tom: Watch the floating piston in the video carefully.....not the one connected to the shaft with the shims...the floating piston with the o-rings separating the gas from the oil....


It moves and compresses the nitrogen behind it because the swept volume of the shock shaft takes up volume inside the shock body when compressed. If you removed all the gas behind the piston or removed the piston and completely filled the shock body with oil the shaft wouldn't compress at all....you would be hydraulically locked.


Yes, you can certainly lower the gas pressure behind the piston for less extension force, but as the video shows bad things happen like cavitation.



The only way to completely remove all of the gas in a damper and have it work is to design it as a through-shaft..that way the swept shaft volume entering the shock body is exactly the same as the swept volume exiting the body...so no delta volume to deal with...and that's how Fox's fancy steering damper works.


..and yes the shims/shim stacks deflect when the piston is stroked to provide high speed damping, with the shims deflecting more at higher piston velocities. That solves the issue using of a simple orifice for damping since at higher piston velocities the damping increases way too much with a fixed orifice.


This is also why clickers on shocks only control low speed compression and rebound damping. The clickers move needles (needle valves) in and out of fixed orifices. High speed speed damping is controlled by shim stacks.

[Vanzila]

I own a 1996 SK Original Owner.. You will not be able to improve the Ride until you replace the Front Leaf Springs with Springs that are not from a Jeep. Sadly thats the biggest issue with the SK vans. Mine had no Bump Steer, ever. But it did turn your kidneys into mush on a basic paved road. I did Add a Steering Stabilizer in about 1999.. But it does not help the Ride. And Stabilizers only work on Highway driving..

contact Ujoint , You will either need to reset the Font end with Larger Leaf Springs.. Or Find a Spring Shop to make some Leafs that Are long enough to absorb.

Ujoint achieves this by Pushing the Front Axle Forward.. This Allows more Travel.. My SK Van had about 7 inches of Travel, Now it has over 15 inches..

[Vanimal]

Originally Posted by Vanzila

I own a 1996 SK Original Owner.. You will not be able to improve the Ride until you replace the Front Leaf Springs with Springs that are not from a Jeep. Sadly thats the biggest issue with the SK vans. Mine had no Bump Steer, ever. But it did turn your kidneys into mush on a basic paved road. I did Add a Steering Stabilizer in about 1999.. But it does not help the Ride. And Stabilizers only work on Highway driving..

contact Ujoint , You will either need to reset the Font end with Larger Leaf Springs.. Or Find a Spring Shop to make some Leafs that Are long enough to absorb.

Ujoint achieves this by Pushing the Front Axle Forward.. This Allows more Travel.. My SK Van had about 7 inches of Travel, Now it has over 15 inches..

That's why I love coils! Having had F150's Bronco's early and 78-79 with radius arms. Several F250's one F350. I would never return to leafs unless it was a Unimog or MANN style roamer and even those are going to air or coil. I know that coils cause bump steer and DW in poorly set up suspensions but set up right they are untouchable by leafs. Leafs help to eliminate DW but at 0 comfort. This weekend at a off road event I spoke with a Fox rep in person. He confirmed my feeling on leafs are a covered wagon mentality proved thru n thru but from Viking days. I must agree with Tom only because prior to the recent years I never remember pressured stabilizers. Rancho had stabilizers that had their own part number. You could not use shocks for stabilizer or stabilizers for shocks. If I remember correctly it was because the pressures were to high for the steering! That is all. I do not want to fill the urinal for either side in this contest!