'yes' is my short answer.
I don't make a point of keeping perfect track of this ..
but there is more than one type of Octane rating system .
one is RON, I forget the other.
There is some chance that the octane rating system that the makers of
that label at that time, is different than the octane rating system
posted on the pump.
  I deal with dozens  of vanagons constantly ..
unless it's some high compression non-stock thing ...( which could need
premium )
all I notice with mid-grade fuel is it runs a tiny bit smoother.

I've seen a million waterboxer piston tops ..
and never any signs of detonation that you can see pictures of in books.
I would drop down to mid-grade at least.
All I ever use normally is 87 octane.
in higher altitude areas their regular is 85 octane.
I use fuel treatments now and then ..
for injector cleaning ....and general fuel system care ..
like SeaFoam ...or Lucas ..
or even Marvil Mystery Oil..says right on the bottle ..'fuel system
lubricant' ..
I do 'something' once in a while,
When I get a new dead vanagon ...or an old one just running, I treat the
fuel immediately.
and I run them on 87 unleaded. They are quite happy that way sure seems
to me.

scott
www.turbovans.com

On 8/23/2012 11:55 AM, Mark A Kippert wrote:
> On Aug 22, 2012, at 12:12 PM, Scott Daniel - Turbovans wrote:
>
>> I am strongly against premium fuel in stock vanagons.
>> If you want more octane use mid-grade.
>> if it doesn't ping, you're ok.
>
> I have to say I'm a bit confused. I run a higher octane in my '87GL because to label next to the filler says (in several languages) to use a min. octane of 91. That would be premium, at least here in Indiana.
>
> Have I been wasting my money?
>
>
> Mark K
> 1986 GL/2WD/4SPD "Abe"
> 1991 GL/2WD/4SPD "Ruby" (sold)
>