bigbird -

Please post pics when you get her done.


I've been trying to figure out what's going on with my vehicle speed vs what transmission and rear end ratios were installed in the car. When I drove her home I was never going as fast as I thought I should be for a given RPM. The car has a late model truck overdrive A833 and 4:10 rear gears. I started putting in the ratios I thought I had into the Tremec calculator and it didn't seem to match up to what I was seeing empirically. I tried putting in 4:55 rear gears and it matched up to what I was seeing at 2500 rpm....what the heck!! I don't know how I wound up with 4:55s...I still have the receipt for the differential, dated 10 years ago. Attached are the calculator results for both gears...any idea what's going on other than I have the wrong differential gears?