I have a 96z that I bought used. It has a flowmaster that I believe is wrong. It has a single 3 in. inlet/ single outlet. Should it have dual outlets? Also, when at very low rpm's just above idle i hear a clicking that seems to be coming from thr rear. What could it be?

The flowmaster can be like that. Usually guys go with the crossflow OE setup but you can do that. You have single exit pipe on one side of car i assume?

As for the rear end noise i can't help ya there, sorry.

yes, I do have a single exhaust on the left side. Also, when I downshift from OD into drive, it feels rougher than it should. Tranny going out?