I personally don't know what the converter can actually deal with and usually don't push it too much seeing as how it's designed to be a cruise gear basically.
I do know I can pull pretty much any hill on freeways that comes up without leaving lockup. (the 5 miles of 6% grade on I17 near Black Canyon City for example)
Chasing a Corvette on I40 at 120 should have put a little power through it though, but that was only about 2,400rpms so it wasn't into the cam power range yet.
