Date: Sun, 19 Mar 2000 17:14:24 -0800
Reply-To: bpchristensen1@HOME.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Brent Christensen <bpchristensen1@HOME.COM>
Subject: Re: Top speed of a vanagon
Content-Type: text/plain; charset="iso-8859-1"
Oops - it looks like I made some mistakes. Let me run it again with a clear
head. Forget about the number I quoted last night, which I got from:
ftp://gerry.vanagon.com/pub/statistics/vw-bus-relative-wear-index.txt
(it is an article by Dave Kautz entitled "Relative Wear Index.)
It really all depends on the rolling circumference of the tire. If you
assume 26" tire diameter. Multiply by pi (3.1415) to get rolling
circumference (APPROXIMATE) = 81.7 inches per revolution of the drivetrain.
Divide into 63,360.1 inches per mile and you get 775.5 revolutions per mile
of the drive train. Now multiply by the final drive ratio (4.571) to get
the revolutions of the engine per mile = 3,544.8
Now if you say that you are going 100 mph, that means that it will take you
60 minutes to traverse that 100 miles. If each mile causes 3,544.8 engine
revolutions, then you have 354,481.1 total revolutions. Divide this by the
number of minutes (60) and you get 5,908.0 revolutions per minute at 100
mph. (I was using a short cut which is obviously based on a different
number for the rolling circumference of the tire, possibly more accurate)
Does a 2WD vanagon turn at 3,544 rpms at 60 MPH? does that sound right?
I think I was way too tired when I ran the numbers last night. (math was
never my strong subject anyway)
God I wish the metric system had taken hold back in the 70's when we tried!
:-)
Brent Christensen
'89 GL Syncro Westy
Santa Barbara, CA
----- Original Message -----
From: Marc Perdue <marcperdue@ADELPHIA.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, March 19, 2000 11:57 AM
Subject: Re: Top speed of a vanagon
> Actually, I believe that 157 kph would translate to about 94.2 mph, which
would
> put the rpm's somewhere around 4823.04. Where did the 3072 figure come
from?
>
> I love this stuff,
> Marc Perdue
>
> Brent Christensen wrote:
>
> > Based on normal gearing in a later model Westy, that would mean that the
> > engine was turning nearly 5,200 rpms (depending on tires). I don't
think I
> > would let her drive the Van any more unless she is making major
> > contributions to an engine rebuild fund...
> >
> > Given that Final drive ratio is 4.570:1 (Top gear is 0.85)
> > Then:
> > (Engine revolutions/mile: 3072 X 100 mph)/60 minutes/hour = 5,120 rpm
> > (unless I am too tired and my math is wrong)
> >
> > In a a Syncro, this would be even worse: 6,083 RPM!
> >
> > Brent Christensen
> > '89 GL Syncro Westy
> > Santa Barbara, CA
> >
> > ----- Original Message -----
> > From: Riley Kettner <rileyk@home.com>
> > To: <bpchristensen1@home.com>
> > Sent: Saturday, March 18, 2000 9:48 PM
> > Subject: Re: Top speed of a vanagon
> >
> > > I know it sounds strange but it was dowhill. not too much though.
> > >
> > > normal engine....
> > > she was a panicking mom rushing to get child that gone on the wrong
> > > ferry.......
> > >
> > > ----- Original Message -----
> > > From: <bpchristensen1@home.com>
> > > To: Riley Kettner <rileyk@HOME.COM>; <vanagon@GERRY.VANAGON.COM>
> > > Sent: Saturday, March 18, 2000 9:41 PM
> > > Subject: Re: Top speed of a vanagon
> > >
> > >
> > > > Unless that was down hill with a *strong* tail wind, I would be
willing
> > to
> > > > testify that it is impossible to travel at that speed in a Vanagon
Westy
> > > > (with normal engine)! Sounds fishy to me...
> > > >
> > > > Brent Christensen
> > > > '89 GL Syncro Westy
> > > > Santa Barbara, CA
> > > >
> > > > ----- Original Message -----
> > > > From: Riley Kettner
> > > > To: vanagon@GERRY.VANAGON.COM
> > > > Sent: Saturday, March 18, 2000 4:45 PM
> > > > Subject: Top speed of a vanagon
> > > >
> > > >
> > > > Dear list members,
> > > > My mom got a speeding ticket in my Westfalia
travelling
> > at
> > > > 157km/h.
> > > > This seems like an impossible speed but it was done.
> > > >
> > > > For the americans, that is roughly 100 mph?
> > > >
> > > > Curious to see what others have travelled,
> > > > Riley Kettner North Vancouver BC
> > > > '87 Westy
> > > >
> > > >
> > >
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