I had posted about this a month or two back. Never found a solution.

Seems like the 83.5-85s would open 130ish degrees, while the later models
only open 90. I agree, Richard, it seems like the screw that pinches the
part that twists is no FaceTime the door outer skin with about 1/4"
clearance.

On Friday, August 8, 2014, Richard Golen <rgolen@hotmail.com> wrote:

> Dave,
>
> Mine will open beyond 90 degrees...probably 120 or 130 degrees. When
> opened this way they act like a scoop to bring lots of air into the cab.
>
> Ric
>
> Sent from my iPad
>
> > On Aug 8, 2014, at 15:26, "Dave Mcneely" <mcneely4@COX.NET
> <javascript:;>> wrote:
> >
> > My wing vents will only open to 90 degrees.  I have often wondered why.
>  Mine is a 1991 Volkswagen Vanagon GL Campmobile, known as a Westy to those
> who like nicknames.  Is the window supposed to open beyond 90 degrees?  I
> wish it would.  mcneely
> >
> > ---- J Stewart <fonman4277@COMCAST.NET <javascript:;>> wrote:
> >> I believe its possible with a pair of needle nose vice grips. This was
> a piece of cake on the Bay window buses as well, why VW changed it is
> anybody's guess.
> >>
> >> ----- Original Message -----
> >>
> >>> Hi,
> >>
> >>> I like to drive my 87 during hot weather with the vent wing opened so
> that it
> >>> blows in cool air toward me. However, once I hot about 45 mph, the wing
> >>> closes...or almost closes. The passenger one does not do this.
> >>
> >>> I know that there is a pinch clamp inside the door to keep this from
> >>> happening. I pulled the door panel, figuring the screw/bolt would be
> readily
> >>> accessible (as it is on my 56 Beetle), but the clamp is way up in the
> door.
> >>> With a mirror, I can see the clamp and it's screw, but it looks like
> its un
> >>> reachable.
> >>
> >>> Is there any way of tightening the clamp?
> >>
> >>> Ric
> >>
> >>> Sent from my iPad
> >
> > --
> > David McNeely
>