if it's performance you're looking for, then you need to decide what you're willing to spend. an exhaust system from headers will be expensive. well over $1000
long tube headers run about 250. they get you the best performance on a Naturally Aspirated motor. shorty headers are cheaper, but lacking in exhaust flow
then you'll need an x or h pipe. off road type will be louder and a little more powerful and costs a mere $190, but a catted h pipe will let you pass emissions, the downside is it costs about $350. if you wanted an x pipe, you'd have to get one custom made or else modified. for the sake of emissions, i'd say get the catted h pipe. check ebay for deals
after than you need to pick a catback dual exhaust. the cheaper brands, like flowmaster, mac, magnaflows, sound pretty good on a v6 without a lot of other mods... all should be between $200 and $400 for the catback
but if you're gonna eventually mod the whole motor, then a higher priced brand of catback may be right for you. there are borla, bassani, steeda... all will run over $400, but when you rebuild your engine, you'll have a nice sounding exhaust
also, remember that you'll have to pay for labor to get all this installed. with headers and h pipe, you'll likely spend over $300 just on labor. if it's beyond your pocketbook, then get the headers later on, just start with the h pipe and catback
but there are the basics you need to know. if you're gonna go all out with your stang, then get all the options. if you just want dual exhaust, spare your pocketbook and get a "cheapie" exhaust. either way you go though, you won't gain more than 10-15 horsepower at the wheels. large hp gains come with engine modding (on v6's, at least)
i hope i broke things down well for you
Thanks
