Hambiskit, Thanks for your continuing advice. I guess what I am asking is whether a 3.70 rear will allow a shift into OD at lower mph than if I use a 3.55 rear gear? I hope Henry Rifle can answer since he has both setups and knows the comparison. It seems to me that shifting into OD at 50 mph rather than staying in third gear of 1.0 will increase mileage while at the same time a 3.70 gear will give tremendous response in low gear. Is the originator of this thread aware that MegaMonster can convert the electrical OD lockup to a hydraulic lockup without wires? Also for the answer to this web question I learned that of the three 700 R4 rebuilding companies I studied, all three would not rate a rebuilt stock 700 R4 as handling over 250 H.P. Maybe this is their way of generating sales for their beefed-up versions, but maybe it is also true that 250 H.P. is a pracitcal limit for a stock 700 R4? I am trying to understand the four speed auto trans. On my Pontiac Sunfire ('98) once it shifts into 4th at about 50 mph you can decelerate and stay in 4th down to about 30 mph before it down shifts, but I do not know the stall speed of the converter in the Sunfire.

Don Shillady
Retired Scientist/teen rodder