That's what I figured. Someone recently told me it was like 80 pounds difference. I know the motor only weighs a couple pounds but I thought maybe the track/mechanism was different.
I am not sure but 20lbs, there is no way. The only thing that really makes a difference in weight between manual and power is the actual window motor, which is about 4lbs. There are some massive side impact supports that run along with the sheet metal that if you were to delete would at least delete 20lbs a door, better have a roll cage with side support bars for saftey.
if one was to the stage of worrying about power guts, i would be thinking it is a dedicated track car and running polycarbonate windows (with the door gutted).
I'm way too big a guy to have ever worried about it though, so i could be wrong.
Power windows rock even on a race only car. You can roll both windows down until you get to the burnout box. Much cooler. Dont have to worry about someone having to help you roll them up.