Once you make the power, you have to put it on the ground... I went to the drag strip this past Friday on my new build and did not hook up for shiz!!! I need a driver mod, I'm rusty!! LOL We have an 1/8 mile strip here and I ran a 9.11 @ 80.... That's good for mid 13's in the 1/4. Back to the driver mod, my reaction time was .887 and with a 2.25 60' with me spinning through 1st gear. This is on my 225/60's running 40 psi and worn out upper mounts. I'll install my poly mounts this week, shift kit, and when I go back to the track I'll drop my pressure down to 18 - 20 psi and take my air tank to fill them back up. I hope to run 8.5 - 8.7 at 85ish which will put me in the 12's. I say this because my LT1 firebird runs 8.9 and 13.1 on stiff, bald 295/35's... Now did I dust shizstangs, you bet ya!!!! Even pissed off a GTI driver... LOL
I didn't mean to ramble, but I'm just making the point no matter the power you make, you gotta get it to the ground. If you have $1500 in your budget and know how to turn a wrench, I'd cam the car IMO. Also, if you can't find a used Plog and DP you really should look into the Speed Daddy headers. They are the best bang for the buck and right now are in stock.
Others can chime in on intercoolers, but how worth while are they on a 3.3 + pulley? Same for the Gen V supercharger. Unless you do a considerable pulley drop, I'd save your money and work with what you got for now. Again my $.02 and I'm doing my times with my mods in my sig and 0 KR.