Date: Thu, 26 Jun 2008 20:19:28 -0700
Reply-To: Don Hanson <dhanson@GORGE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Don Hanson <dhanson@GORGE.NET>
Subject: Re: Syncro bad handling problem Now some weight stuff...
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Weighing fore and aft is easy and it's instructive to know so you can adjust
how you add things or load your van. Weighing each wheel's load..that is
another 'critter' altogether. That process is known as "corner-balancing"
in the racecar world and has to do more with ride height adjustment than
weight.
Think of your van as a table or chair with one leg too long(or too
short)...That table rocks on the two opposite corners leaving one leg or the
other of the opposite corners always up in the air. Which one is
unweighted depends on whether you're braking or accelerating...
Vehicles have springs, so this 'un-even' load is somewhat masked (unlike a
table or chair), but when you put scales under all the wheels, you usually
find that rocking table-type condition. The fix for that is to adjust the
suspension to even up the loads, corner to corner. Like cutting off the
long leg on a rocking table or chair.
On a racecar, looking for every bit of traction available and for
predictable handling, having an even load, corner to corner, is quite
helpful and can be adjusted with very small changes in how your vehicle sits
on it's springs. Unfortunately, Vans don't have adjustable suspension
perches.. On my 84 van with it's inline four mounted at 50 degrees to the
left, I noticed it was pretty wacky on it's springs. Going uphill on gravel
or snow, my right rear spun at the slightest touch to the accelerator until
I inserted a spacer at the top end of that spring to "push down" at the
right wheel more...Kinda crude, but it is a van, not a formula one car.
Those NASCAR boats have threaded adjustments the crews can turn during a pit
stop to lift or lower a corner..thus adjusting the handling of the car.
They are changing the "corner balance". In our vans, we can do some good by
loading it properly also.
So if your Syncro has gained a lot of weight on just one corner, two
corners are not getting much of the load...Makes for weird behavior. Like
driving a 'rocking table' as you brake, turn, accelerate etc. A difficult
concept to 'see'..
One way to help visualize what's happening to a vehicle during suspension
loading is to take a couple of pencils or pens and cross them in one hand.
Now, rotate your wrist and hand and watch what happens to all the corners,
in relation to each other. Even the slightest move changes all four
corners, right? Think of your van's tires as those four ends of the
pencils and you will get an idea of how the weight/load moves as you turn,
stop, accelerate or combo...
A very interesting exercise, trying to learn how to make a suspension work
better..There are many books but it's also somewhat of an art.
Don Hanson
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