Having thought about all this interesting and exciting worry about the
accuracy of our speedometers, I think that I might fix Matilda's. I
remember it breaking its drive cable in '82 on the way to Washington D.
C. As the speedometer is primarily a social device, and not monitoring
any engine function, so it is not really that important. In serious
rallying you would not rely on it, and in most club rally situations a
good navigator can certainly overcome the need for it. Now the oil gage
is important, but a working speedometer would be cute.
Chuck Harris
Waltzing with Matilda at light speed
On Tue, 21 Jul 1998 08:07:49 -0400 "DeLuca, Joseph"
<Joseph.DeLuca@wl.com> writes:
>
>
>I agree with getting a second opinion about the speedo calibration,
>but as a old-time rallyist I wouldn't trust anything other than a
>stopwatch and a measured mile.
>
>My favorite method is to find a fresh stretch of highway. One that
>hasn't been torn up too much, because they tend to rearrange the
>mileage markers when they do construction.
>
>Motor along at exactly 60 mph which translates to one minute per mile.
>Measure the time. If it takes you 66 seconds to travel one mile
>(which ideally should be traversed in 60 seconds) then calculate
>66/60 x 100 = 110% (as an example).
>
>Try this at several different mileposts to get an average because,
>as I said, the highway dept (and intoxicated drivers) move the markers
>around a bit.
>
>For the best accuracy I prefer to visit the local cop shop and ask
>where THEY calibrate the police car speedos.
>They usually have a measured mile somewhere in town. The only
>downside is that they often start to ask you a lot of questions.
>They think you want to organize drag racing there or something, and
>if you let slip that you have a "sports car" you're in for it.
>Tell them you're training for the Olympics (although with my frame
>that's a stretch).
>
>If the measured mile is in town and you can't do 60 mph conveniently,
>the factor for 30 mph is 120 seconds per mile, and for 45 mph it's
>90 seconds.
>
>Happy Motoring
>
>Joe DeLuca
>Sparta, NJ
>'62 yellow 4/4
>
>
>
>-----Original Message-----
>From: John T. Blair [mailto:jblair@exis.net]
>Sent: Monday, July 20, 1998 5:23 PM
>To: morgans@Autox.Team.Net
>Subject: Re: Speedometer calibration
>
>
>At 06:05 PM 7/19/98 EDT, you wrote:
>
>>My neighbour and I were exercising our Morgans on the highway last
>week
>>at what seemed to me to be a legitimate speed when we came upon a
>>gendarme parked on the median. My friend slowed dramatically.
>>Afterwards I asked why he had slowed when we were doing only 65. "We
>
>>were going close to 80" he replied. I had always thought my speedo
>was
>>reasonably accurate.....
>
>John,
>
> Are you sure that it was your speedo that was off? Before you go
>nuts
>trying to get your guage calibrated, take another, late model car, out
>
>and chase it. Instruct the driver of the late model car to signal you
>
>with 5 fingers and then a fist at 50 mph. Then when you wave back at
>him, have him move up to 55. Again signal you with 5 fingers flashed
>2
>times. Repeat this procedure for 60 - 1 finger held horizontally and
>a
>fist, and 65.
>
>This will let you know that it was YOUR speed o that was off and not
>the other Morgan you were chasing.
>
>John
>
>John T. Blair WA4OHZ email: jblair@exis.net
>Va. Beach, Va Phone: (757) 495-8229
>
> 48 TR1800 65 Morgan 4/4 Series V
>71 Saab Sonett III 75 Bricklin SV1 77 Spitfire
>
>
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