Daniel, yes you are correct, the Van should have C rated tyres.
I am not sure on your rim width, but my 82 has 5 inch rims, so a 205 series
tyre is to wide for this rim, the tyre would have excessive "roll" on the
rim. You would need a 6 inch rim  width or larger for a 205 series tyre,
check your alloys, the size should be on them somewhere.
When I first bought my Westy it also had standard car tyres, I brought C
rated tyres and the improvement was significant. But then I had the
advantage that the standard tyres were at the end of their life! I have to
say I would have been inclined to run them untill they needed replacement
due to cost.
The wallowing problem could be a combination of your tyres and several other
things
1. Worn shocks
2.Front stabiliser bar problems( I have had the link arm from the suspension
wishbone to the actual stabiliser bar break)
3.General bushing wear.
I am sure others on the list would be able to add to these comments.
Hope this helps
John.
----- Original Message -----
From: Daniel Schmitz <djs@GENE.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, May 24, 2000 6:33 PM
Subject: Tires (a tired topic?)

> On my recently acquired '87 Westfalia, the tires do not appear to be the
> correct type for this vehicle.
>
> They are General "Ameri" branded, 205/70R14, Standard Load Rating
> radials, with a max inflation pressure of 35 psi.
>
> Based on what I've read on the list and what I bought for my '82
> Adventurewagen, I think I am supposed to be running LT,
> sidewall-reinforced tires with a Load Rating of "C".
>
> As further evidence, my Westfalia tends to wallow and really lean in the
> turns, as well as being very sensitive to cross winds, even more so than
> my Adventurewagen, which has a higher center of gravity.
>
> The one downside is that these tires are relatively new, and I would
> have to sacrifice good, though incorrect, tires for new, correct ones.
>
> The option to swap tires with those on my Adventurewagen is not really a
> possibility, as those are mounted on stock steel rims, and I definitely
> want to retain the alloy wheels I have.
>
> Anyone care to comment?