[Mustang_GT_90]

If you're wanting to go faster there is a lot of stuff that you can do which is relatively cheap depending on how "hardcore" you are into going fast.
Sorry I don't mean to sound like a know it all on this but I mean I've done this twice now and it's one of those deals you learn your mistakes and try to do it right the second time.

1. Do a good tune up: Plugs, maybe wires, filter, make sure cap is good, make sure coil is firing good. Then set your timing up to around 14 degrees you'll be amazed at the difference. Make sure your throttle body and stuff is clean, clean it out with a bottle brush and some carb cleaner.

2. Remove the air silencer. For now don't worry about ram air and don't get a normal conical filter it's going to suck hot air in from the engine compartment. They've done tests and with a K&N panel filter the stock air box with no silencer has been proven well over 300 horse.

3. Make sure your car runs as cool as possible. I run a 160 degree cheb thermostat in mine. Lots of people say that's to cold but it works good for me. I live in Kentucky and we have pretty cold winters and 100 degree summers and it's been working pretty good. You don't need to like shell out of the hypertech, a normal 160 or 185 chevrolet will work and it's $6.

4. If you don't need it running off the engine then get rid of it. Parasitic load is BADDDDD. This one of those how "hardcore" are you deals. Sure underdrive pulleys help but there are some trade offs. I'm about to get rid of mine now becuase I'm tired of the alternator discharging at low RPM and I"ve got a G3 alternator.
If you can in your area drop the smog pump, not that it's draining power but it's weight on the front end. You can bypass it at the track with a 70 inch belt using the A/C pulley as an idler. I gained .2 in the 1/4 from that alone. Does your A/C work, if not why keep it, dump it. My truly hardcore freinds are running like a 34 inch belt that only runs the water pump and alternator. You can take the hoses off the stock power steering rack and run it, I don't suggest it but you can do it and it really turns a lot easier than you'd ever imagine.

5. Another thing people overlook is electric fans. I'm running a normal autozone special 16" electric fan. It cools my car fine and I was amazed how much quicker it revs up top when you drop that stock fan. That should be with the whole parasitic load thing.

6. Weight reduction, if you wanna go fast drop weight from the car, every 100 pounds is .1 in the quarter which is equal to having to have your motor gain around 10 hp. This is a freeby so that's why I threw it in up here. Stuff like sound deadening you can trash. We got 100 pounds off a car in just removing sound deadening and spare and jack and stuff. This is another "how hardcore are you thing though"

7. This is where you start to spend money, mufflers and exhaust and stuff or what I"d suggest is gears before exhaust. I went 13.90@98 with just gears through the factory exhaust 4 cats and the works and didn't gain that much with aftermarket exhaust after I did it.
If you do exhaust though do a good flowing X pipe and a set of something like flow masters. I don't know if this point if I'd say go headers or not because you don't really have enough motor to need them.

GEARS. Gears are the bigest kick in the ***** you can give a car, if you've got airplane gears and go to like a 3.73 then you'll be in for a big jump in acceleration.

8. Making it hook, by this time if you've been going good and if you've got a 5 speed car you're gonna be hauling and also spinning pretty bad. You're gonna need some kind of tires or something. A good set of drag radials or cheater slicks. It doesn't do you any good to make power if you're gonna be spinning.

9. SPRAY IT Spray the heck out of it. Nitrous is the most bang for the buck and depending on how much of a shot you go with on a stick set of tires by the time you've done all of the above you should be WELL into the 12s.

Like I've said above, I know that not everybody is gonna agree with this and I really don't mean to sound like a know it all guys. I don't want to start an argument. I've done this all before and I've just thrown money away and seen what worked and what didn't and I spend a LOT of time at the track.
I've got most of the mods done above and as you can see in my signature I'm running 13.30s on motor and spraying 12.40s and my car isn't stripped or gutted it's close to full weight. When I get done with weight reduction there's no telling what it's gonna do.