We dyno ours through all the gears...We start in 1st punch it and let it go all the way up to OD and around 72 mph then we let it coast to idle...then put it in part...i suppose you could always dyno it like a manual if you have a torque converter controller...start in first go to redline then shift it manually into 2nd go to redline then shift to third and go to redline...having OD off. Four speed autos third gear is 1:1 and thats why fourth is OD 1.79:1.