I have discovered that the speedometer reads 3 to 4 MPH faster than actual. The man at West LA Automotive Center explained that the manual specifies that calibration. He said he could correct with a resistor if I wanted to send back to him. Of course that would take another couple of weeks down time, Tn. to Ca.. If one uses this company, I guess you should specify that you want the speedometer to read TRUE. Who wooda thunk it?