I say do a single 3" into a Hooker Header Aero Chamber muffler, and then dual out of it. It will give you a great sound, and it has the best flow of all those mufflers. However, if you do not want the Hooker, then go with the classic single in /dual out Flowmaster 40 series. Great sound, but doesn't flow as well as hooker.
Both of these will be coming off a y-pipe. True duals isn't necessary to get a performance increase. The above setup will work just fine, and run ya about $250. All you have to decide is if you want the pipes to exit out the rear, or out the corners at a 45 degree angle. I prefer the corners so you can hear the exhaust better, but you may like the look better of the straight out the back pipes.
Ron
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