A while ago, I inquired about a speedometer issue that gave me a 15-20%
over indication of speed.
Well, after talking to a few local guys and listening to the list, and a
lot of number crunching, I found the problem. The wrong speedometer!
For those inquiring minds, the correct unit for a stock US TR6, (i.e.,
standard tranny, 3.7 diff, 'stock' tires) seems to be a unit with 1120
turns/mile. I do not believe that there are different drive shaft
counter gears available and all calibration is taken up in the unit.
Since Simths was (is) a popular supplier of speedometer units for
British cars, I'm sure that there are a number of different variations
out there. You might want to double check before picking up a used
unit.
Now I am looking for a little more info. The unit I pulled is a 1000
turns/mile. The only TR I can match this up with is a PI TR6 (i.e.,
standard tranny, 3.45 diff, 'stock' tires). Can anyone verify this is
correct? If so, I am quite happy (i.e., NOT looking to sell), as I
wanted to swap to the 3.45 r&p on the next rebuild.
Scott Mackay
Austin, TX
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