Just wanted to find out what everyone thinks the first absolute must do upgrade should be. I prob will take to a shop to have done and am not looking to spend a fortune. $250-1000 max.
Ive heard air intake and exhaust are good first mods.
The stock TB will perform as well as any other aftermarket TB out there as long as your not aspirated or heavily modded internally so strike that off your list.
The CAI & tune is the biggest bang-for-the-buck (roughly 15-25+ RWHP, mod dependent). THAT you can install yourself or be considered not worthy of owning a Stang (j/k).
I'd go with gears, UDP's, aluminum DS and then consider some wheel, rubber and suspension mods to help keep that power hooked-up in preparation for the SC!
The stock TB will perform as well as any other aftermarket TB out there as long as your not aspirated or heavily modded internally so strike that off your list.
The CAI & tune is the biggest bang-for-the-buck (roughly 15-25+ RWHP, mod dependent). THAT you can install yourself or be considered not worthy of owning a Stang (j/k).
I'd go with gears, UDP's, aluminum DS and then consider some wheel, rubber and suspension mods to help keep that power hooked-up in preparation for the SC!
+1. CAI/tuner with a tune and pullies. You may even have enough left for some lower control arms to help get that extra power to the ground.
I would definitely start off with CAI / Tune which is ~$600. If you want to spend all of your left overs, I'd get a set of axlebacks - All of which you should be able to install yourself so no need to worry about the expense of labor.
C&L or JLT intake with Bamachips or Brenspeed tune, 3.73 or 4.10 gears, and axle back exhaust. That will be your full $1000, maybe a little more depending on labor costs and brand of exhaust.
Let that pony breathe!!! Not sure if you want to do it at a later date or not but consider this. Save $2000, buy a set of kooks headers with the x-pipe( i have the one with no cats) and a tuner ( i personally used a Diablosport) and you will be surprised at the gains you get. I know thats twice as much as you want to spend but you will be VERY VERY GLAD that you bought the headers and x-pipe. I run a friend after install that had a tuner and CAI and I beat him on the track and doing roll ons on the highway. But if you insist on getting something now then I would suggest CAI and tuner that would be your best bet.
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05 Mustang GT - Performance Mods - Kooks Long Tube Headers, Kooks X-Pipe (no cats), Magnaflow Magnapacks, Diablosport Tuner
Appearance Mods - 20" Shelby Razor wheels (Gunmetal with polished lip), flat black fender stripes
O by the way I would steer away from throttle bodies. I talked to the guy that tunes my car and he told me that throttle bodies were a waste of money. He showed me dyno sheets from past customers and cars typically made 5rwhp tops but only about 3rwhp. But its your choice. Good luck with your car and your mods.
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05 Mustang GT - Performance Mods - Kooks Long Tube Headers, Kooks X-Pipe (no cats), Magnaflow Magnapacks, Diablosport Tuner
Appearance Mods - 20" Shelby Razor wheels (Gunmetal with polished lip), flat black fender stripes
A few folks have already said it best, and I have to agree. Cold air intake with custom tunes and axel back exhaust. I like to get to know the car a little bit before jumping into big mods, so I would recommend not getting too crazy at first. What year is your car and are you still under warranty? If you are, then you'll probably be better off running CAI/tune/exhaust for the time being. Unless, you're not worried about voiding the warranty, in which case, go all out.
2006 GT performance upgrade first thing 
