Date: Wed, 26 Oct 2011 19:29:35 -0700
Reply-To: "Danny C." <bruiserbabie@YAHOO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Danny C." <bruiserbabie@YAHOO.COM>
Subject: Re: Aerodynamics related to fuel consumption (for an 84 tin top)
In-Reply-To: <006801cc943b$8a9e1920$9fda4b60$@gmail.com>
Content-Type: text/plain; charset=iso-8859-1
Sorry all I have been sick this week. I will stay away. But I did like all the tech talk on roof rack systems. We have some smart people on here... Keep it going......
Danny C.
Portland, Oregon
'84 Westy (Vanny)
________________________________
From: Andrew Martin <ramblinvan@gmail.com>
To: 'Danny C.' <bruiserbabie@YAHOO.COM>
Sent: Wednesday, October 26, 2011 5:01 PM
Subject: RE: Aerodynamics related to fuel consumption (for an 84 tin top)
Gee Dude. Why so rude? :-(
Yes, please do go back in time... Back to the night you were in my driveway
complaining about 14 mpg. Remember? I certainly do.
Glad you are doing well but...
Andrew
Bainbridge Island WA
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Danny C.
Sent: Wednesday, October 26, 2011 3:59 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: Aerodynamics related to fuel consumption (for an 84 tin top)
Let me know when you install your flux capacitor. I need to go back in time.
Danny C.
Portland, Oregon
'84 Westy (Vanny)
________________________________
From: Poppie Jagersand <poppie.jagersand@YAHOO.CA>
To: vanagon@GERRY.VANAGON.COM
Sent: Wednesday, October 26, 2011 1:56 PM
Subject: Re: Aerodynamics related to fuel consumption (for an 84 tin top)
________________________________
From: Danny C. <bruiserbabie@YAHOO.COM>
Sent: Monday, October 24, 2011 10:18:37 PM
> Seriously!!! your worried about what drag there is on a roof rack. WOW!!!
The difference in air resistance coefficient between the regular Vanagon, Cv
= 0.44, and the Vanagon Westy with the front roof rack, Cv=0.51, is a
significant 14%.
Many of our vans have gone 200,000 miles or more by now. Over that distance
the difference in Cv translates into about 1000 gallon additional fuel
consumption. (Assuming 20mpg, mostly highway driving, and air resistance is
60-80% of total drag: 200000/20*.7*.14=1000)
When independent labs published these Cv numbers in magazines VW removed the
front roof rack on the European market Westys (model years '89-92), and
replaced it with a more aerodynamic profile reducing Cv back to 0.45, nearly
as streamlined as the original Vanagon.
Maybe if the North American consumers had been more cognisant of the
accumulated cost of usage VW would have offered the same improvement here
also.
For aftermarket add-on roof racks and accessories designs vary as well as
the vehicles they are tested on. Reported fuel economy impact vary from a
low of a few percent up to 15 % for some racks and 25% for rack and bicycle.
Martin (and Westy Poppie with poorly designed roof rack :(
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