what is the difference between an auto tranny flywheel and a manual tranny flywheel?

 

Manual flywheel is thicker, heavier, and has a clutch bolted to it. Similar to a brake rotor. I the auto flywheel is thin and light weight.

 

would u gain anything from getting an aftermarket flywheel for an auto tranny?

 

I doubt you could find anyone who makes auto flywheels. You will gain more benifit from a higher stall rate on the torque converter. The flywheel is already really thin and lightening it would cause structural problems/failure. Most only weigh between three and five pounds anyways.

 

Your flywheel hardly weighs a single pound. I just took mine out of my F22, and I was surprised at how small it is. If I get a chance at weighing it, I'll post the weight.

 

...and flexible, which is why it's called a flexplate instead of a flywheel.