An interesting comment to this test..not from me
Its almost impossible to accurately answer this question. In the past some numbers were issued to it but how they came up with the numbers is beyond me. There are too many variables, including converter design , converter charge circuits, trans ratio , axle ratio, vehicle weight , motor max RPM, shift rpm.
Some transmissions in some applications will take more power to run but you can't just say its 20hp VS a glide, no way.
The losses will be greater if the parts used in the trans are a larger diameter , so all we can say for sure is the smaller the diameter of the parts used , the less power the transmission will require to run and thats about as far as it goes.
Don't assume that because one trans is heavier than another , that its all rotating weight either.
The powerglide is an efficient design and the internals come to speed progressively ,All 3 speeds have anti rotation to deal with (parts have to reverse then stop then start again) for a shift sequence and that takes time and power to do.
