Bill:
    Your main problem is that the van behaves like an arrow flying
backwards.  It has the center of pressure ahead of the center of mass.  The
solution is to move mass to the front, or area to the back - like a giant
tail fin on a boom 10 feet behind the van.  Gene Berg did testing like this
way back when, but the result is silly looking.  I notice that when using a
trailer, the problem is greatly reduced.
    The practical approach is to keep the steering tight - ball joints and
tie rods, bushings, correct tire pressures, alignment.  Sway bars help
control the response times, but don't solve the underlying problem of
aerodynamic instability.  Good shocks are a must - I like Bilsteins.
    Spoilers front and rear are marginal devices really, for the speeds we
travel at.  I made a front air dam for my '71 bus in college for a senior
engineering project.  Found out that the center of pressure on the front was
lowered about 6", but the drag was reduced only 3% - well inside the noise
of measurement.  The downside is that you can't enter ANY driveway without
scraping.  No good to society.
    Good luck.
        Randy

Bill Urban wrote:

> Hello all,
>
> Just got back from an Easter trip to S. Illinois and had a hell of a
> time on the highway. For 3/4 of the 460 mile trip the van was being
> pushed around by terrible crosswinds.  It was very difficult keeping it
> on the road.
>
>  These were very serious winds. This storm system had torrential rain
> and caused one tornado in Wichita,KS (my destination). I saw 2 semis
> wiped out on the side of the road that I assume were victims of the
> gusts.
>
> What, if any, are my options to make my van less vulnerable to these
> blow monsters? My van is a '91 Carat. It has a front airdam, new Sears
> shocks, and new Yoko Y370s ( I'm questioning my choice of these over the
> wider Mich MXTs). Someone on the list mentioned a rear anti sway bar so
> that is in my van's future. One idea I had was a rear spoiler on top of
> the van for downforce. Is one of these made for the vanagon
> (projectzwo??) and how much are they? Any ideas that can help with the
> wind problem wil be greatly apprecated.
>
> Later, Bill