i'll still say that exhaust is the first thing any one should get when modifying a stang. gears won't add any power, just accel quicker. i mean don't get me wrong gears are a great idea, and who doesn't want to go quicker, but i think that should be second on the list. a set of headers u can get for about $200-$250, a offroad h-pipe(keep the stock pipe for inspections) for $115, and a cat back for about $200-250, depends on the brands, and stay with the same one, mac is pretty good. u don't really need a 130 amp alt either. i run underdrives with a stock alt and i have never had a problem!
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89 GT AOD w/ shift kit, B&M rachet shifter, Trickflow intake, Crane (E-type) cam, 70Tb, 75MAF, 1.6 Rockers, Pulleys, MAC headers and H-pipe, Dynomax mufflers, K&N, 3 core radiator, custom interior, cobra R rims
MY89GT