Date: Tue, 7 Jul 1998 11:58:47 -0400
Reply-To: Derek Drew <drew@INTERPORT.NET>
Sender: Vanagon Mailing List <Vanagon@vanagon.com>
From: Derek Drew <drew@INTERPORT.NET>
Subject: Doughnut Height Measurement Data
Content-Type: text/plain; charset="us-ascii"
Here is some additional data that may be helpful.
I went out and measured the ride height of the van. (I followed the factory
method of measuring the distance from the center of the rear wheel axle
[center of the hubcap on my alloy wheels] and the lowest point on the
fender above.) This measurement in the right rear of my Westfalia is 48.5 cm.
Three extra doughuts should raise the van 3.3 cm, according to a
measurement of their thickness, minus about a 10% discount for compression
and their hollowed out place.
Therefore, we can get another list owner with a Syncro Westfalia to get a
weigh and find out that they weigh 5,150lbs. total and then measure his
ride height at and compare it to mine. (Ideally, to allow for equal wear on
the springs, they would also have about 85,000 miles on the van, about
1/5th of which were severe off-road miles in a heavily overloaded vehicle.)
If my spring is extra-compressed, and hence has more tension on it, and
hence has some extra compression than a normal Westy, then their Westy
should measure about the same as mine, or about 48.5 cm. But if my spring
has the same height as a regular Westy Syncro spring, and hence is not
compressed, and has no additional pre-load, and carries the same
springyness as a stock van, then they should get a measurement of about
45.2 cm. I have about 300 lbs of stuff in the back of my Westfalia (winch,
jacks, cargo carrier on roof, closets jammed full) and four doughuts per
side. My vehicle now weighs about 5,150lbs.
So how about it, Syncro Westy volunteer? (Non-Westies do not qualify
because they do not have the same weight patterns). (Jim Davis is
disqualified because of having had his springs streached, and Steve you are
disqualified because you already have an extra doughnut.)
At 12:48 PM 6/30/98 -0700, you wrote:
>Derek:
>I can say "wrong" too. And you, my friend, are wrong. I have explained
in great
>detail why. Don has now chimed in with an equation that shows why the
spring is
>stiffer if pre-loaded. Simply saying "wrong" does not cut it. If you do not
>address the issues, there is no discussion and no progress.
>Look at the YZ manual. http://www.concentric.net/~Sxs/preload.shtml
>Are they wrong, too? If not, what's the difference between lowering the
spring
>perch on the YZ and lowering the spring perch on the syncro? And if adding a
>spacer does not accomplish the same on the syncro, what would accomplish
pre-load
>on it? After all, I thought the issue was how do we do this to tune the
>suspension and thus improve it, not who's right and who's wrong.
>steve
>
>Derek Drew wrote:
>
>> My comments are sprinkled below...
>>
>> At 11:12 PM 6/29/98 -0700, you wrote:
>> >I will kill this thread if requested. However, it is an important topic
>> >and the issue at hand remains unresolved. This post proposes a means to
>> >resolve the dispute. It's worth the effore because if adding a spacer
>> >pre-loads the springs, then there's a cheap, relatively easy and
>> >accurate way to tune the suspension...balance it...and yes, improve it.
>> >In fact, there should be no dispute that you can accommplish these goals
>> >by pre-loading each wheel to the optimal level of spring
>> >pre-load/suspension sag given the weight the wheel bears and the damping
>> >provided by the boges. The stock set up is not the optimal set up, but
________________________________________________________
Derek Drew New York, NY & Washington, DC
drew@interport.net
'90 Syncro Westfalia...
...seen off-road at http://www.tiu.net/~des/vw/drew/index.html
Also seen at: http://www.pipeline.com/~tforhan/swrange.htm
http://4wd.sofcom.com/VW/snow.html
http://www.pipeline.com/~tforhan/swmassn.htm
http://4wd.sofcom.com/VW/Campers/Campers.html
Note: most valuable Vanagon sites on the planet (for owners) are:
http://gerry.vanagon.com/cgi-bin/wa.exe?S1=vanagon
ftp://gerry.vanagon.com/pub/
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