I am thinking abouot going with a 4l80 but I already have a really nice 4l60 Circle D 4c converter.

 

Two totally different converters. You will need to get an 80 converter for the 4l80e. They have different input and stator shafts to start with. Also the converter hubs are different because the two transmissions use different style pump gears. Sorry to say but it sounds like you now have a converter for sale. Vince

 

Vince is correct - will not interchange. Different hub, stator splines, turbine splines, height and bolt pattern.

Chris

 

oh yeah and the 80e converter weighs 620 lbs compared to the 4L60e haha