The major purpose of the dyno test is to test the Nox reduction system.
It usually isn't required for 80 and older vehicles. 81 was the first
year that Nox had to be controlled to limits that required O2 sensors
and 3 way catalytic converters. The water cooled Vanagons do not have
EGR so the Cat is extremely important for Nox reduction. Changing gear
ratios and over advanced ignition timing are also contributors.

Dennis

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Larry Alofs
Sent: Thursday, August 18, 2005 10:58 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Best chance of passing emissions?

Try to get more info about the test.  In Chicago they use a dyno for
older vehicles, but they don't test for NOx.  My '80 used to pass with
no problem and its cat was hollow.
   Traditional dry-gas is methyl alcohol.  It can be bad for some parts
of the fuel system, so I wouldn't leave it in there very long.
   Change the oil. Check for vacuum and exhaust leaks.  Be sure the air
filter is clean or remove the element temporarily.  Don't let them put
the front wheels on the dyno like they did with mine once.  :-)
   Good luck,
Larry A.

Christopher Gronski wrote:
> 48 hours the test. I dont necesariy have to pass but  get complicated
> if I don't. My cat is in place with the o2 sensor, but apparently is
> hollow. My exhaust is a new (three week old) S&S header system.
>
> Chris
>
> On 8/18/05, Dennis Haynes <dhaynes@optonline.net> wrote:
>
>>Is that 48 hours to take a test or do you have to pass it? If you are
>>getting a dyno test, most likely you will need the cat for the NOx.
Part
>>of the test.
>>
>>Dennis