My 1972 reads 140MPH when 100 is correct. (The mile markers on the Freeway read 1.4 miles apart on my speedo). Looking at Pantera manuals there were two speedos available 1200 and 1610 rotation per mile. My Pantera doesn't have a 90 deg drive at the speedo end either. My conclusion is the either the transmission or speedo were changed and the 90 deg drive ommitted. So I now have the wrong combination and lack a 1.1:1 90 drive at the speedo This would give a 1610/1200x1.1= 1.47 error, close to the error I actually see. Can I solve the problem by replacing the driven gear in the ZF and buying a 1.1:1 90 drive? Or are they not interchangable between transmissions and I have to find the correct speedo?
Is there a source of other ratio 90 deg drives, that would fix the problem in one go?
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