I am going from efi to carb and i was wondering what is needed to do the swap the car is a 92 gt and is not daily driven? the current mods are below. thanks
1. A carb (obviously). Holley is recommended for their insane tunability. I'd say a 600 or 650 double pumper since you have MT. For some extra gas milage, go vacuum secondaries (holley street avenger 670). Smaller is better or you will have no vacuum signal and it will run like crap. I went from a 670 to a 600 and _what a difference_.
2. An intake. I have the edelbrock performer and I am happy with it.
3. Distributor. The TFI equipped stock unit will no longer work. Get an 85 mustang distributor or an earlier 302 unit and a steel drive gear. The gear is crucial since the iron gears will _shred_ within a day or two.
4. Ignition system. Get a duraspark or something like an MSD unit that will hook up to the magnetic pickup on the distributor. Get a coil too, you might as well, theyre cheap enough
5. Timing chain cover that accepts the mechanical fuel pump. FMS has one. The stock one has the depression but the back panel is not cut out and the two holes are not tapped for the bolts. It could be modified I guess.
6. Eccentric for the cam to drive the pump
7. Mechanical fuel pump. Dont go electric!!! I tortured myself for weeks trying to get the pressure right with not one but two inline regulators. Save yourself the grey hairs and make the fuel system mechanical as well as the motor.
8. Drop the tank and replace the fuel pump with a length of hose clamped onto the top plate's tube. Make the hose slightly longer than necessary to reach the bottom so it turns sideways when it hits.
Then spend a gleeful weekend ripping out 25 pounds of wiring and sensors. Keep one O2 sensor and get an A/F guage so you can tune your carb. I think you'll need to lose the oil level sensor I think. I think the AC also has a computer controlled clutch so you will need to goose or strip it.
You will thump yourself on the back after you do this swap. You will never regret it and you can laugh at people when they do the "what the hell is wrong with my car" or the "what maf goes with what injectors goes with what computer goes with what tb" posts. You just turn some screws and are back on the road 10 minutes later. And what a clean enginebay!!!
There is also a clean EFI system, a throttle body that looks like a carb so you can have that classic "airfilter in the middle" look. I think they run around 2500$ for a complete system and can be tuned using a normal laptop computer.
You can also install an inline fuel pump such as a Holley Red (constant 7psi) or Blue pump (up to 14psi with a regulator). Just place it behind the tank and use the existing fuel line to feed the carb (no return line).
or you can just use a hi volume oil pressure regulator to keep your existing fuel setup (for now), also just found out that MSD makes a stand alone igniton setup that doesnt need the stock computer, comes with dis, and ignition module for around $450.
If you haven't bought a carb check out Quick Fuel Technologies. They are former Holley engineers that have gone out on their own. They make a real nice vacuum secondary 650 called the ProVac. Its very streetable and great at the track. I picked up 2 10ths right out of the box. It looks like a Holley and tunes like one, and the best part is its about $50 less the the Holley.
Their sight is www.quickfueltechnology.com