Date:         Fri, 4 Jul 97 23:08:31 EDT
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         jag@cs.rochester.edu
Subject:      Re: Formula for calculating speed w/given gear ratios

> I know there's someone out there with a handy dandy formula for calculating
> top end for different gear ratio's and rear ends. This is for my `82 Westy
> Diesel. Anyone?

I wrote a (very simple) matlab program, which draws a speed-engine_rpm
graph for the different gears. An example graph is on:
(This graph is using the gear and final drive ratios from my diesel 4sp)

	http://www.cs.rochester.edu/u/jag/vw/engine/gearrpms.gif 

The program + a table of ratios for the 68-91 type 2 gearboxes +
a table of tire diameters (useful for corrections if you don't
run factory standard tires) is in:

	http://www.cs.rochester.edu/u/jag/vw/engine/gearrpms.m

To run the program script you need matlab. 

To calculate optimal final drive for a different (stronger) engine
a torque-rpm curve and some knowledge of the drag of the vanagon
would be useful. Does anybody have this for the 1.9 TD?

/Martin

PS: Do you know about the VW-diesel list? Email Tom Guptill for
subscription information: tgpt@pas.rochester.edu. Or Tom, can you 
post it to the vanagon list?

Martin Jagersand                 email: jag@cs.rochester.edu
Computer Science Department             jag@cs.chalmers.se
University of Rochester 

        Slow down and visit the VW diesel Westy page:
          WWW: http://www.cs.rochester.edu/u/jag/vw
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