Thanks guys!! The catch can catches the pvc oil so it does not re-enter the intake thus leaning out the fuel mixture. This long term can build up in the intake and cause the car to retard the timing. I am not sure how much of an effect it has, but Diablosport recommends it so I just put one on based on their comments.
FYI....here's what the beast looks like right now. It waiting on the new converter to arrive.
As soon as it get here, the trans is going back in and off to the strip we go!!