[Vwdiesel] Speedometer question

[Chris Geiser]

I run 205/60/15's (Michelin Agilis) on my vanagon and the speedo is pretty
accurate.  Even though they are 15's, I want to say that those are pretty
close to the original tire circumference when I checked it out.  As they
have worn (probably close to 75,000 miles on them), the speedo is a little
fast (reads faster than the van is actually going).

Chris

-----Original Message-----
From: vwdiesel-bounces at vwfans.com [mailto:vwdiesel-bounces at vwfans.com] On
Behalf Of dieseltdi at verizon.net
Sent: Thursday, August 02, 2007 1:21 PM
To: VW diesel mail list; diesel Vanagon Yahoo group; tdi conversions news
list news list
Subject: [Vwdiesel] Speedometer question

I am mulling over various tire sizes  for my Westy AAZ TD conversion   
to bring down the rpms in relation to the trans (1.14 3rd and .7 4th)  
and I got to thinking about the speedometer.  As I recall, the number  
on the face of the speedometer is the number of revolutions per  
mile.  Am I right on this?  The speedo in my Westy is marked with an  
820, since it gets its revs directly from the hub, on revolution of  
the tire, should equal one revolution of the cable and one revolution  
of the speedo gear, right?  Why all of this?  Well a 185/75/14 tire  
has 834 revolutions per mile but a 195/75/14 has 815 revolutions per  
mile and a 205/70/14 gets 822 revolutions per mile.  Any thoughts on  
any of this and which tire size may be best?  Of course all three  
sizes are LT or C rated tires.  Hayden

" Those who are willing to sacrifice Liberty for Security, deserve  
neither Liberty nor Security."  Ben Franklin
"Dictatorships all have common factors:  a government controlled by  
one party, a leader who claims to have special powers outside the law  
to keep the country "safe", secret prisons where people are locked up  
without charges or trial and government opponents are branded as  
unpatriotic and charged with aiding the enemy."

Visit my website at:  http://mysite.verizon.net/resosxp8/mydieselpages/
Proud owner of:
2007 Jeep Grand Cherokee CRD (My newest diesel aqcuisition)
1998 Jetta TDI (Wetterauer Chipset, 2 1/2" exhaust, K&N Filter,  163K 
+ miles, and running biodiesel)
1982 Vanagon Westfalia Diesel - "THE SLOTH"
And many, many, many VWs; from a 1946 Beetle (11 Beetles total), to  
Vans (5 - 3 splitties, 2 bay window), Rabbits (3), Karmen Ghia (1),  
Jettas (5), Passats (2), Dasher (1), New Beetle (1), and Rabbit  
Pickups (3) most now gone but not forgotten.



_______________________________________________
Vwdiesel mailing list
Vwdiesel at vwfans.com
http://www.audifans.com/mailman/listinfo/vwdiesel