If it is that critical, you could always but a Smiths Electronic Self
Calibrating Speedometer ..
On Mar 20, 2012, at 1:30 PM, Geo Hahn wrote:
> On Tue, Mar 20, 2012 at 11:17 AM, Hdefer <tr3 at roadrunner.com> wrote:
>
>> ...Haven't figured how to easily calibrate it at higher speeds yet, but
>> at least it is perfectly steady all the way to at least 80 mph.
>>
>
>
> We use a GPS -- I call out the speed as I drive and my wife keeps a charts
> of GPS v what I call. Leave the head unit loose and pull into a parking
> lot to open it for quick small adjustment.
>
> Of course the error is often non-linear so perhaps the best you can do is
> make it very accurate at a speed that is important to you and settle for
> fairly accurate everywhere else.
>
William Pugh
anabil007 at comcast.net
|