04 Stock GT want to upgrade cams

Hi TKStang04,
If your only going for sound and that nice lope then stage 2 comp cams would be a nice addition. Let me warn you first. Anything above stage 2 and your talking major modifications to the heads due to clearance issues. I have stage 3 comp cams and I had to replace my heads for them to work. The heads alone were $2400 that I needed. Little did I know the cams I bought wouldn't work on stock heads so my $600 dollar project quickly spun out of control and cost me about $4,000. Go with stage 2 comp cams and have a shop professionally install the cams. I would buy a tuner and have a shop professionally tune your mustang after the cam install. Cams allow more air into the combustion chamber by increasing the duration of the intake valve. More air means you need more fuel to properly combust inside the motor. You can drive it without getting a professional tune done but it would probably have weird idle issues, deceleration issues and problems under full throttle. Hope this helps and makes sense. I would guess with stage 2 cams, labor, a handheld tuner, and a dyno shop to tune it for you, your looking at around 2,800. Right under your budget and done right!