ADVENTURES IN ADJUSTABLE SPRING PLATES

[r1cpowdercoating]

hey FJ,
After further pondering the topic of these spring, I got to thinking. (this could be dangerous) If the spring plate is flexing, is not the trailing arm moving? If you replace the spring plates should you not replace the trailing arm with an aftermarket style that is built a lot more beefier (?) to stop the flexing? also replace the stock bushing with the red neo style. This should take all the side to side flex out of the rear end. along with a good sway bar.

ron

[FJCamper]

Hi Ron,

On a swing axle, the spring plate is the "trailing" arm. Different from an IRS, where we have a genuine diagonal arm, attached to a spring plate (double or single).

The adjustable spring plates we've just installed in the swing axle Mexico Ghia do not have the side-to-side flex of the stock parts, and with the strong urethane bushings inside and outside, virtually no front-to-rear movement. They just pivot upward a little.

This makes for a much stiffer rear suspension overall.

We use a camber compensator U-bolted to the outer ends of the rear axles to further stop unwanted movement.

In short, making a swing axle handle on a race track means keeping it from moving as much as you can.

FJC

[r1cpowdercoating]

long live the IRS!!!!!!!

[r1cpowdercoating]

hey ya'll I found a little better way to adjust the rear spring plates. useing the old screw compressor is aggravating and dont work very well. however, if you take a piece of chain up around the torsion housing and back around the jack. then as you jack the spring plate up it pushes the jack down and the chain holds the car down. I used this method with a strap. it worked very well.

ron

[rsb]

Hey guys,

I was curious:

The top of the "tool" coming off, is that due to weld failure at the nut or cup, or is it the result of that nut unscrewing during use? I was thinking spot welding the nut to the rod might be worth the time lost.

Does placing a clamp (or vise-grips) on the trailing arm to keep the "tool" from sliding cause any problems with binding that would require moving it at any point in the process? Do you place the tool on the downhill side?

I am sure that these issues would be pretty clear when I get that far on this project, but I prefer learning from other peoples experiences.

Thanks for the great info.

Brian

[Ol'fogasaurus]

If you are talking about the cup that threads onto the rod at the top and has some welds to hold it from backing off; one of my “tools” did that also so I welded it back on but made better welds this time. Don't put too much heat into it though as threaded areas are much weaker than non-threaded areas.

“Does placing a clamp (or vise-grips) on the trailing arm to keep the "tool" from sliding cause any problems with binding that would require moving it at any point in the process? Do you place the tool on the downhill side?”

Since the resistance load is being applied on the down-hill side of the “tool” by the torsion bar and spring plate, the “tool” is going to want to climb/slide up-hill to towards the pivot end of the spring plate. When it goes there is no warning and it goes pretty darn fast.

Don’t forget to get a second nut and use a wrench on it; use the Winged-nut as a locking device only not a working tool. It will save you a lot of work and frustration. Also a drop of lube in the threads from the bottom up; as I remember those threads are cut threads and the material is fairly soft so you will get a lot of wear, w/o the lube, in the short time you climb the threads with the nuts alone. Use the floor jack as much as you can to compress the spring plate onto and off the stops. Let the torsion bar slowly relax as you lower the spring plates with the jack. If the torsion bar is allowed to unwind on its own it is violent and blazingly quick so keep out of the way; you will have no time to react!

Some people, and I tried it in a lazy moment, try to use the “tool” to do all the work but you sure do work and you sure do see the threads wear. You can do it but you will also spend a lot of time at it and the “tool” will wear out quickly.

Lee

[rsb]

Thanks for clearing that up Lee!

On my tool the part that hooks onto the body bolt is just threaded onto the rod, which seems pretty iffy as things that can thread on can also thread off. I am definitely going to pick up a couple washers and a real nut for the tool. Good call on using the jack to save wear and tear... I have a 3 jaw puller laying around that beautifully illustrates the effects of too much load on dry threads.

-Brian

[Ol'fogasaurus]

I usually go get a tall head bolt to install in the body bolt location. It takes some of the "Iffy" out of it but you still have to watch it.

Lee

[vwo60]

I have a suggestion when installing the spring plates, i had a set of swayaway adjustable spring plates on my 70 beetle, very good quality, the ones i have seen laterly are a poor imitation of those, the easy way of fitting them is to back the adjusting screw out and you can just about lift them onto the stop by hand without the tool, then adjust them level when you have fitted the end cap and bushes, on the adjusting grub screw, the internal hex on mine started to fail a short time after installatiion because of it's limited size, i simply replaced it with a socket head cap screw which has a much larger internal hex, there are no clearence problems as the head of the cap screw is still smaller that the tapped block that it screws into, no more issues

[Steve Arndt]

How fast will these fail on a dual purpose baja?

Impossible to answer I know, but has anybody actually had them fail besides the adjusting bolt mentioned? I searched and found Porsche 911 aftermarket adjustable plates of this design fail from side loading and the plate slipping off the adjuster block/screw.

Steve

[FJCamper]

Adventures in Jackscrews

Well, our swing axle jackscrews have held up, but we had a near-immediate problem with our IRS road racing Super Bug, the notorious Blitzwagen.

What happened was the left hand jackscrew just locked up after one race! No adjusting. And all there was to move it was a small 6mm hex in the screw. We broke one 6mm wrench trying to turn it. Many bad words, a half-inch drive 6mm hex, propane heat, and hammer banging finally got out the offending screw. The problem seemed to be a banged up thread or two and just plain rust.

Use a good smear of anti-sieze on yours.

The photo shows what we replaced both sides with. Easy to turn.

So far, so good.

FJC

[PhillipM]

question on the adjustable, how many miles have you logged? i have heard stories from off roaders (both mean and mild) that the adjustable threads tend to beat out pretty darn fast leaveing them non adjustable. road courses I am sure are much nicer to them, and I would kind of like to do this upgrade.

Yes, seen that with a couple of buggies over here, a better setup is to have clamp bolts between the two halves, which you tighten to clamp the two halves together after using the adjustment bolt for fine tuning.

[Bonemaro]

How many inches of adjustment would you say these give you over and under factory ride height?

[Ol'fogasaurus]

I am not excited (nor do I expect to be popular with my opinion) about the adjustable spring plates. I was warned away from them when I first got into VWs because many I talked to thought that they were problematic. Maybe minimally OK for minor adjustments as I know some racers are getting away with it in some racing but with the possibility of hammering/mushrooming the bolt ends and also the bolt threads walking down the threaded part of the spring plates. You could also damage threads on the nut part of the spring plates if the material or temper isn't right. Also, there doesn't seem to be any jam nuts in the assembly... that I am aware of.

I think adding the adjuster in the center of the torsion tube might be better but then you can not set different preloads to either side of the car as easy as you could with the ones in question.

Not familiar with VW Road Racing that much but had talked to some ACVW racers many years ago.

Lee

Correction: I remembered the center adjuster being one pieces and the torsion bars were adjusted together. It has been pointed out to me that that is not true. I looked some up and I stand corrected. They do look stronger but still not the best was to do things I think.

I also corrected a word for and to can.

Lee

[PhillipM]

Yeah, we had those until we cut 'em out, 2 fingers with adjusters and locknuts, one spanner and an allen key and you could adjust both sides of the car without getting out of the seat.