I recall seeing numbers posted from Car Craft putting them roughly in order from least to most HP loss:
PowerGlide
200-4r
T350
700r4
T400
4L80
but don't quote me on this.
I figure if I want an auto I'm going to have to sacrifice power.


'53 BelAir 261 3spd/OD 4dr
'54 3100 235 3spd
'79 C30 with a '51 235-'57Bellhousing-'67SM420-14bolt dually
'89 V3500 350/465/205 SRW CC
One Chevy just isn't enough.