Asking for a friend.
1966 GT350 with T10, 3.50 rear gear and 14 wheels & tires.
At true 30mph his speedo reads 35.
At true 60mph his speedo reads 70.
In round figures that calculates to a 17% error at both speeds.
I think the gear on the end of the speedo cable that goes into the trans has 17 teeth.
Does he need a speedo gear with more teeth or fewer teeth? Anyone know exactly how many teeth would correct this error?
Thanks,
Steve