Date:         Fri, 1 Dec 1995 12:50:27 -0500
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         drew@interport.net (Derek Drew)
Subject:      Syncro Vanagon lifting Brainwork

John, 

Your idea to weld a 2nd tube under the existing shock mount tube is
brilliant--an elegant, simple solution. I imagine the existing welds which
hold the bottom of the shock onto the stock tube could be strengthened
somehow as well, either by additional welding or by something like the 1/8"
strap that you refer to. I measured the distance between the shock and the
driveshaft last night and the distance is about half the width of my finger,
so whatever is devised in this vein must clear this obstacle. I am going to
collect more data on this issue tonight.

I also find the idea of the aluminum spacer you mentioned excellent and
elegant too provided that the indents on the aluminum spacer can be made to
simulate the indents in the factory flange on the shock, and, for strength,
that the spacer not be split at any point--that it, that it not become split
apart the way a loc washer is.

The question as to which of these two methods to employ seems really the
tradeoff:

1. increasing the driveshaft excessively 

vs. 

2. descreasing suspension travel.

If the cost were not too much, I might seek to split the difference--a sort
of 50/50 approach--and employ *both* mods, assigning each to perform half
the desired 4.5mm difference. 

An argument against performing both mods is that the double shock tube setup
you designed below won't allow such a small adjustment as 2.25mm and that it
might be expensive and time consuming to make sure it is safe. 

Accordingly, I have the idea to have the offset washer/shim manufacturered
that you mention, and if I desire additional suspension travel, I can always
achieve this by adding a washer/shim piece *above* the shock. I'm wondering
what the correct thicknesses should be for the new spring washer and the new
shock washer (for the upper mounting point of the shock) to achieve the idea
50/50 approach I'd ideally like to take.

Now, before work on this can begin I have to confirm that there is no easy
way to place a rubber or thick metal washer *above* the spring. If the above
can be accomplished, then I can do it myself without having to fabricate
such an odd offset washer to go *under* the spring. I think the answer may
be that a washer of only 2.25mm will fit in there over the spring without
bringing about the danger that the spring will come out of its seat, but
that a washer of 4.5mm would be too much in this regard. In this case, I am
looking at making a 2.25mm washer to go over the spring and a 2.25mm washer
to go over the shock. 

I realize I didn't send you the mounting pieces that go over the shock (they
are a part of the vehicle body!) so you'd be unable to see exactly what is
going on in this regard.

I'm going to try to get a good look at this this weekend. I'll be back next
week.

>Derek, the other thing that concerns me about raising the lower mount by
>attaching something to only the current mount point is this.  I too
>thought well why not just even do something like this, weld another
>circular tub the same size as the gurrent tube to the bottom of the
>current tube (tube that holds the mounting bushing).  Since current one
>is welded onto the shock, a good quality weld would be more than
>sufficiently strong.  Then further as the stress is now transfered to
>that current tube which is hollow, press in a solid steel bushing to
>support load, and maybe gusset on each side by welding some 1/8" or so
>strap up over both on the sides.  problem is this, whatever you do as
>long as it only attaches to the current mounting poin, NOT the shock
>tube, relies on the strength of the current welds between the bushing
>tube and shock tube.  Now as most loading is tension or compression and
>mostly compression at that not an immediate problem, bu  whatever side
>loading exists (which admittedly should be nearly none as side
>positioning is handled by the suspension geometry) is trying to bend or
>shear those current welds.  This worries me as by adding something to
>the bottom you increse the torque arem to those welds increasing the
>stress on them, and frankly they are not that impressive to begin with.
>
>anyway to detail I imagined this
>
>     |          |
>     |          |
>     |          |
>     ____________
>       /      \  <- this the critical area of current welds
>      /        \
>      |        | <- the old bushing mount filled by solid steel or
>      \        /    boxed in by welding plates over sides
>       \______/ <- welds here need be no stronger than origional
>       /      \
>      /        \
>      |        |
>      \        /
>       \______/
>
>
>But back to your spring mount shimming idea (the typical raising method
>though it does reduce travel.)  What if I say could have fabricated
>something that looks like a giant split lock washer, out of 1" thick
>aluminum.  Sort of a flat aluminum washer/donut then cut and pressed to
>offset it the 1/4" or so.  This seems to be no great task to me
>and gives you a quick easy way to raise.  I don't know however how much
>more than about 1" thick you could go, but still even that would largely
>restore a correct ride attitude.
>
>John
>ja@coe.wu.edu
>
>
>
___________________________________
Derek Drew
drew@interport.net (main address for e-mail)
derekdrew@aol.com (alternate/backup address, checked infrequently)