Date:         Wed, 20 Jan 2010 20:30:03 -0500
Reply-To:     mcneely4@COX.NET
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dave Mcneely <mcneely4@COX.NET>
Subject:      Re: van aerodynamics,
              was Re: BenT's dream vanagon now for sale
Comments: To: Jim Arnott <jrasite@EONI.COM>
Content-Type: text/plain; charset=UTF-8; format=flowed; delsp=no

But, the original question was how the camper did compared to the
pictured vehicle with a poptop but no luggage rack.  We don't have a
drag illustration showing a vehicle like that.  How do we know it is
better, worse, or the same as the camper with the luggage rack?

BTW, the only stuff I've ever put up there was a rafting dry bag once,
and firewood another time.  No cooler or lawn chairs.  David Mc


On Wed, Jan 20, 2010 at 7:09 PM, Jim Arnott wrote:

> The big hole where the ice chest and lawn chairs go upsets the
> airflow.  Roger's California had the cowling the eliminated that hole
> and it was noticeably cleaner. The luggage rack causes the boundary
> layer to separate immediately behind it and become turbulent.  That
> increases drag.
>
> http://www.thesamba.com/vw/forum/viewtopic.php?t=316411&highlight=drag
>
> Jim
>
> On Jan 20, 2010, at 10:31 AM, Dave Mcneely wrote:
>
>> Granted that common sense fails often on many fronts.  But I'd like
>> to
>> know, if indeed it is the case, how the vehicle with a pop top but no
>> luggage rack would be more aerodynamic than the more typical
>> camper.  If
>> the airflow is smoother over that top, I'd be surprised.  But I've
>> been
>> surprised before.  In this case, I'd just like an explanation, so I'd
>> understand better.  David