DISCLAIMER: I am not discussing vehicle current draw, just vehicle driveability.
Ron brings up a critical point.
Pretty much all vehicles are dependent on the motor's top rpm and the car's final drive ratio.
As Ron said- My 2,000# car and 32" tire likes a 6.14 gear and the AC50's top RPM (6500+). It works by having a 2,000# car and the RPM
to give a good top speed.
A powerglide will also work on a torque brute like the Warp 11 or 13, in a similar car. When they are geared for their top RPM the final drive works out to be a shorter 3.55-4.10 (depending on tire size). This combination works by having enough torque to cover the bottom end
The powerglide would be a poor choice for a smaller motor (AC or DC), or a heavy vehicle (3,500 Lbs and up) or hilly country if you want a top speed over 40 MPH.
Heavy haul trucks have an 18 speed transmission for a reason. To suit the motor torque to the hill and vehicle weight. Electric power is a lot like Diesel power, it has good torque over a narrow RPM band. Gear accordingly or you will be disappointed.
Ivansgarage is building a GMC Sonoma. He is using the original 4L60E transmission. It will work nicely in the truck which will be 3,500Lbs and up in weight. It is still converterless and retains the automatic shift features.
The water cooled AC motor being mocked up with the 4L60E transmission.
The motor specs are not public yet, but it is about 1/3 over an AC50 in torque. This and the 4 speeds will make this a really nice driving combination.
You can kill a nice install by "cheap skating" the gearing. (Trying to make do with what is in the vehicle.)
is in the gearing for your situation.