TritonTR20

I'm considering putting Magnaflow mufflers on my 2007 GT, but am concerned about what that would do to the performance or if I might even get a check engine light if I leave the factory tune on it. I'd prefer to continue using 87 octane, and keep the factory tune. I don't have a tuner, and don't really want one since they seem to require that I use high octane gas. Can I get the new mufflers without a retune? Thanks.

Evil 5tang

You do not have to get it tuned to change axelbacks, however if you choose that you want to go and get off road mid pipes or something like that then you will most definately need a tuner. Also you do not have to run higher octane than 87 if you want a tune, almost every shop has a 87 performance tune that they can make for you. However I highly recomend getting a cold air intake and 93 octane tune because it will wake up your car like you wouldnt believe, but its your money and your car spend it how you like.

burtoniii

No you dont need to retune, you can also get a cold air kit w/o a retune. I would recomend you also get the cai. Once you put these two on you get better gas milage plus about 25 more horse power you can defenently feel. And if you put a tune for 91 or 93 octane you'll pick up even more with those two in combination. Lets say you have mufflers and a cai vs a stock GT and race from a dead stop, by the time you hit 60 mph you will have about 2 car lenths on him. If I were youI would get the cai first because when you put mufflers on first, your engine will get rid of exhaust faster thus putting more sucking on your restictive air filter thus putting some performance lose at some rpms. But do some looking on ebay and as many performance stores and you can get both as low as 150 bucks depenging on how you want your set up. Check out HOTTEXHAUST.Com for the cheapest magnaflow mufflers and bad *** tips. If you put two magnaflow magnapack mufflers with the 2.5 inch core applyed to the center of your car and buy crome tips for the rear it will be cheaper than buying axle back mufflers and will look better. Or if you want louder and not so mellow at idol than the magnaflows go with the slp axle back crome tips which is prettymuch a no muffler system. Check out YOU TUBE.comand type in mustang exhaust clips to hear almost every kind of exhaust set up.