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RE: high rpm @ h-way speed

Has it occurred to anyone but me that the speedometer difference may be due
to wheel size? While you can't say exactly, since wheel size doesn't
precisely map to tire outside diameter, if you divide 16 by 15, you get
roughly 7% error, which works out to 5 mph at 70 mph vehicle speed. It seems
to me that, even though the gas door says 15" wheel, the car was originally
designed or set up for 16" wheels and somebody "forgot" to change the gear
in the speedometer. Conversely, Michael may be running 16" wheels on a car
that has a speedo set for 15" wheels. It's a thought.

Paul Meyers 87 5KCStq 130K mi 5spd

-----Original Message-----
From:	owner-quattro@audifans.com [mailto:owner-quattro@audifans.com] On
Behalf Of Michael Williams
Sent:	Wednesday, June 09, 1999 11:38 PM
To:	Gary Kaklikian; 'Kurt Wesseling'; paulm@viewsoft.com
Cc:	'quattro'
Subject:	RE: high rpm @ h-way speed

Gary Kaklikian decided to speak these words:

>Mine's the same way - I think they all are. 75 actual is about 83
>No wonder we all think the type 44 cars are so fast - 140 indicated is
>probably only about 128 actual.
>No excuse for a speeding ticket - right?

My car is the exact opposite, 65 indicated is actually around 70.  When
im at 3k it says im doing about 67-68 and im actually doing around
74.5...  I figured out the math...

so, its bad, now i finally figured out why i have gotten 2 speeding tix
in this car...the speedometer.  Im going to use this info to fight my
most recent one...we'll see what happens...


Michael Sheridan Williams
San Francisco, CA
ICQ# 11740998
1983 UrQuattro, MC--1.8 BAR, borla, 16x7.5 OZ Mito's w/ SP8000's, K&N
1985 4000S Quattro, Koni Yellows/Coilover (2B), strut brace, Sport 8000
Tires, K&N