Step1: Open hood, Step 2: throw away air silencer(snorkel), Step 3: close hood, Step 4: enjoy 5-8 extra hp for free!
Then use that cash to free up airlow through the exhaust pipes via midpipe and a low restriction muffler setup with no cats and mil eliminators. Good luck-
for $200 I'd do a 70 or 75mm throttle body and upper plenum. You won't gain much peak horsepower but your power and torque curves will broaden some, especially on the bottom end and the throttle response will become razor sharp and lightning fast.
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Sometimes I think that government fits that old-fashioned definition of a baby: An alimentary canal with an appetite at one end and no sense of responsibility at the other.
- Ronald Reagan
For 200$ I would perform a basic tune up. Considering it's an 96'.
Basic tune up would be new plugs(40$), high performance coils(50$), new k&n filter(50$),an STP fuel system cleaner(10$),and some new synthetic oil. Been there done that, a basic tune up in my opinion is more important that bolt-ons, and it's a proven way to restore lost horsepower.
All good points... IF it has had a tune up recently then I would say the TB/ Plenum or a short throw shifter. The stock shifter is pretty weak. Throw an aftermarket shifter on there and enjoy quicker, more solid shifts that can actually help your track times.
American Muscle has cheap CAI kits for less than $100 that clean up the looks of your bay as well as giving you a bit more throttle response.
Just some thoughts...
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66 Coupe Tahoe Turq - 200, Pertronix & Flamethrower, 3 Row Rad, Cliff. 6/2 96 GT Vert Laser Red - FMS pulleys, Bullet ProM, BBK CAI, Prof. Prod. Elbow and 70mm TB, MAC Off-Road H, Borla side exhaust, Tokicos, B&M Ripper, 18x10 & 18x9 DD Bulletts 06 GT Tungsten, UIP, Red Leather, Stick, 18" blades, Steeda CAI, SCT XCal 2 w/ MC Racing 91 tune, MACs, BMR SP010 springs, BMR Adj Panhard, CDC ducktail & quarter louvers, Rear louver, painted black stripes
Personally, on my 96 I first bought motorcraft plug wires, then a CAI from american muscle and followed up with the tb/plenum. I can definetly tell the difference. Plus the amount of air being vaccumed through makes it sound like youve got a supercharger on there. THe CAI only costs bout $90, the plenum however. Its round $420 for a good brand like mine(accufad from American muscle).
1996 Mustang GT, Need some advice. 
