"65 2+2, 289 auto, 2.7 diff: I checked the cable gear which is a 16 tooth (right). At about 62-3 the speedometer is showing 70. I installed 215-70-15 tires hoping the error would diminish, but no luck. Looking into the tranny hole at the inner drive gear it appears to have 8 teeth. Calculating the correct cable gear it comes out as needing a 14 teeth gear. Not made, at least in the catalogs. Did they make a 8 tooth drive gear and a 14 tooth cable gear at one time? Really would like...

Speedo error compensation