make 6 1/4 mile passes with sticky tires. Switched diffs at the strip (from the stock 3.69 to one with the 4.10s already set up). I'm going on memory (not always good), but we threw out the high and low run of each and averaged the ET and MPH. The average with the stock gearing was 14.5 and the average with the 4.10s was 14.1 with an average increase of 4 MPH. There is an old thread somewhere about it but I didn't look for it. FWIW, Mark