There's also Eastern and Bosal cats. Eastern is high flow, not sure about Bosal...never even heard of em.
I got a direct fit (meaning with a y-pipe) Eastern cat for my '01 ram at rockauto.com, no complaints. It fits good and sounds loud with a flowmaster.
But if your not gonna replace the y-pipe (you might as well if it's rusted to all hell) you should just get a universal magnaflow and have a shop weld everything up.
Last edited by Matt Nickerson; 04-17-2012 at 07:22 PM.