need help with upgrading my 8 1/4 rear end.!

Converter recommendations come with a known cam, and engine perameters as well as car weight and gear ratio and intended use.

I myself went here for a custom built converter which is no more expensive than one from the bigger companies with the same power ha doing capabilities.

Mine was ordered with the future in mind with anti ballooning plate, billet covers etc....
The fellas that built it stated;
"It's good until 650 HP, no problem!"

Here is there web site which also contains an order for that you can veiw. It is similar to other places that do this kind of work. The more you can fill in the better off and easier it is to get what you need. They are also racers themselves, so, if you lack some info, it's really not a huge problem. You just have to know where your going & where you want to end up with how your doing it.

ProTorque High Performance Drag Racing Torque Converters

My transmission was done by this guy here on Long Island. He is and has been very well known for decades around here for ace work. Freedy Brown "fbperformance"
high performance, 4r70w, transmission, AOD, racing, Freddy Brown
The Mopar page; Mopar Transmissions