Need some advice on headers a y
 

I was planning to get nonemissions Pacesetter coated long tube headers and ORY pipe. I have a wide open Borla catback. Will this combination sound bad? Would a GMMG catback be better with it? Should I get high flow cats?

Its going to be pretty loud and possibly somewhat crackly at higher RPM's depending on what else you do to the motor-

If you like it ridiculously loud then go for it-

LOUD=FAST right? go for it!

Not necessarily...
IMO a GMMG would sound better than the Borla. If you do not have emissions, then don't worry about putting on the Hi-Flow cats. The Pacesetters are a good decision. I have a set of the non-emission long tubes and the ORY. Some of the best money I ever spent so far. Now I am going to true duals in the next month or two.