Since there is always a lot of questions(and I get a fair amount of PM's) on swapping a 4g63 into these trucks I figured I would make a sticky post with info on what is needed for the swap and what needs to be done/modded. I might be missing a few things but I'll edit them in later as need be.
Engine and engine wiring harness/ecu:
*DOHC 4g63/t from preferably a 90-92.5 Mitsubishi Eclipse/Eagle Talon, Plymouth Laser. 93+ 7 bolt engines can be used but are not usually desirable as they are prone to crank walk.
*Complete engine wiring harness, ecu, and mpi relay from the same year range vehicle as the motor. When performing the swap you get rid of the trucks engine harness completely and slap the 4g63 one in its place. You will need to shorten and lengthen some wires since engine is now positioned different than it was in the car. You then need to give the ECU and MPI Relay power and also wire the mpi relay to your fuel pump to run it, etc. A wiring diagram with what needs to be done and info thread can be found HERE thanks to the 4g63 swap guru Jeremy at hotrodcoffeeshop.com. Be sure to join his forums and read up on builds to gain more knowledge.
*Narrow block pattern KM132 5 speed(older 4 speed KM132 will also work) manual transmission from 83-89 Mitsu Mighty Max/Dodge Ram50 trucks with the g63b 2.0. To assure you have the right tranny measure the center to center distance between the two lower bellhousing bolt holes and it should be around 12.5". wideblock trannies(which you dont want) measure around 13.25".
*Bill Hichner on the projectzerog.com(Also a great source for info on 4g63 swaps) forums makes tons of bellhousing adapters for a bunch of different transmissions also. Anything from Toyota R154 to GM and Ford trannies if you want to go that route.
Flywheel/clutch/pp for KM132 setup:
*Front wheel drive flywheel and pressure plate from same year range vehicle as motor. You will want the center hole on the flywheel machined a little bigger to fit the trucks pilot bearing for added reliability.
*Clutch disk from 87-89 2.0L truck. If you plan on making a lot of power then I suggest buying a custom made clutch disc and maybe converting to a hydraulic clutch.
*Mighty Max/Ram 50 2.0L truck motor mounts will allow the 4g63 to bolt right into the trucks, but you will need to do some beating and/or cutting of the firewall to make room for the thermostat and cam angle sensor on the back of the head. If you don't want to mess with the firewall you will need to make/modify the stock mounts to move the motor forward about 2" to make room, but then you will also need to modify the transmission crossmember and lengthen the driveshaft to accommodate the 2" the power train moved forward. If you don't want to do that you can get a water housing outlet relocation kit(Jay Racing makes a commonly used one) to mount it to the front of the engine but there is additional modifications required. Check out the projectzerog.com forums to find more info on what needs to be done to do this.
*Water pump: You will probably want to use the 2.0L truck water pump so that you can easily route the hose from your radiator to the water pump. Doing this requires some grinding of the ribs on the outside of the water pump to make clearance for the 4g63's timing tensioner parts. You need to have the 4g63's water pump pulley pressed flatter to align it with the alternator and crank pulley. For the water pipe coming out of the back of the water pump you will have to weld on barbs/fittings for hoses to be connected to for the turbo,oil filter housing, and throttle body water lines
Pic of truck water pump clearanced for tensioner parts:
*Intake manifold: You will need to cut off or make a new flange to be welded onto the front side of the intake manifold for the throttle body and make a plate for the old spot.
Pic to show intake manifold. You don't need to add the extension, it just made it easier for my setup:
*Turbo: The turbo needs to be rotated 180* on the exh. manifold to route the exhaust out to the back and the intake to the front of the vehicle. You will also need to reclock the turbo center housing so the oil drain points straight down and you can also reclock the front compressor cover to point the compressor outlet any which way you need it. New oil drain and feed lines will need to be made and also new water lines. You will need to buy an o2 housing flange and make a new exhaust down pipe for the turbo.
*Thermostat housing cover: You can run the thermostat housing cover from a Mitsu with the 1.8L(4g37) motor. It will point the outlet away from the firewall like the stock 4g63 cover and towards the side of the motor for easier hose routing.
1.8L bottom 4g63 top.
If you have any questions or even more info just post and I'll add it into the thread.