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TR6 TR6 Speedo guage

TR674

Jedi Warrior
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Hello all
I took my speedo guage to an instrument specialist to clean and service as the indicator was jumping excessively.
Now that I can read a steady indicator, the speedo over reads, approx 75km/hr at an actual speed of 60km/hr.
Interestingly, the guage face has a number of 1100. Apparently this relates to 1100rpm/mile. I suspect I may have a speedo from a non overdrive TR6. Can anyone confirm the number on the face of their overdrive model speedo?Regards
Craig
 
My '73 TR6 w/factory overdrive (US Spec) has 1120 on the speedo. Can't be 100% the speedo is original but I suspect it is. It seems to read reasonably well although I have not gone out and paced it against another car to confirm it.

Ken
 
Someone once posted the different numbers on the speedos and which cars and transmissions that they related to. Keep in mind, that there are also two possible rear axle ratios, the 3.70 and I believe a 4.10 to 1, which will also affect the reading of the speedometer, if the driven gear in the transmission is not matched to that ratio.
 
Paul
how can I check which axle ratio I have on my car?
Regards
Craig
 
My mistake. The ratio's are 3.70 to 1 & 3.45 to 1. There is s number on the differential housing and as soon as I find how each number relates to the ratio, I'll post back.
 
Found an old spec page that says 3.7 was USA carb and 3.45 was PI.
 
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