Where to go next

gears! then maybe intake, throttle body, MAF, injectors with heads and a cam?

If you have 5sp then no worries, slap 3.73's in and don't look back, lots of auto guys use those too, i went 3.55(with auto) just to drop it a few hundred rpm, but dollar for dollar there is no better upgrade

How much is done to the car already? If it's stock and you are looking for a place to start, you can choose to follow this list:

First mods should be as follows (my take):

In order of Priority
1) Subframe connectors (SFC's) full length ones are prefered for a stiff chasis
2) Gears: 3.73:1 or 4.10:1 seem to be the popular choices
3) Full Exhuast (headers, hi-flo cats, catback +mufflers)
4) Buy a K&N panel filter (no CAI kit required) and put it in the stock box
5) Bumped timing to 12 - 14 degrees (free mod) 10 Degrees is stock.
6) Larger MAF, TB (MAF cars from 1988 california only, 1989-1993)
7) 3G alternator upgrade / electric fan
8) Fix the weak brakes

Optional MODs:

9) Strut tower brace (necessary on Convertibles IMO)
10) Underdrive pullies (they can't be used on S/C motors and cause charging problems)
11) Weight reduction out of the nose of the car
12) Shocks/Struts and lowering springs
13) C/C plates if you lower the car
14) Short throw shifter (if you have a manual transmission)

After those (the basics), it's pretty much up to you. There are plenty of Super Chargers or Heads, Cam and Intake packages to choose from.

Also, don't forget about the basic tune up
1) Changing all of the fluids (oil, coolant, trans, rear end, brake and some of the power steering)
2) Plugs: (non-platnum type) Autolite or Motorcraft are prefered
3) Oil filter: Motorcraft or equivalent (not FRAM)
4) Air filter: see first mods item #4
5) Plug wires: Ford Motorsport (FRPP) 9mm units are great
6) Cap / Rotor
7) Oxygen sensors

Quoting someone very smart "You need a good foundation before building the house"

Lemme guess? JR, huh?

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