Hello

I am looking for some upgrades to my 2003 mustang coupe. Im not looking for cheep but just some improvements in horsepower and performance. Any advice will be excelent.

 

Search around there are tons of these topics. But gears will be your best bang for buck mod.

 

First do a catback and air intake. Then do headers, rear end gear (your gt only has a 3.27 from factory), and a tune. Whether or not you're going to get longtube headers determines what type of midpipe you'd need.

 

+1... This is a good start. Gears and tuning will be most noticable though