Explorer Gt40 Motor Into My 90 Gt Questions

BKM48198

15 Year Member
Jun 7, 2008
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Ypsilanti, Michigan
I bought a 96 Explorer motor and am going to put it in my 90GT, before it goes in it will get TFS Valve springs and my stock HO cam and new timing gear set. What are the differences between the engines, which parts should I use between the two motors, are the injectors better on either motor or are they the same? What about the smog parts, I don't need to be smog tested and might just take that stuff off, but I don't want to have problems, any help with Vac. lines that need to be used or capped would be appreciated. This is a daily driver not a race car. Is there any thing that could save me a headache later on, any advise is helpful.
 
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The 96 Explorer EGR works the same as the 86-93 Fox 5.0 Mustangs.
The Explorer intake manifold vacuum routing is a little different, but not difficult to manage. The Explorer intake swap tech note below will help you get things working..


Explorer intake swap.

The ACT (Air Charge Temp) sensor will probably need to be moved. The early Explorer/GT 40 lower manifold isn't drilled & tapped for it to go into the intake like the stock manifold was. There is a boss cast into the early Explorer/GT 40 lower intake manifold, but a machine shop will have to drill & tap it. Use a 37/64" drill and 3/8 " pipe tap for the ACT sensor. The best spot for the ACT is the air box if you don't do the drill and tap thing. You get to cut and splice the 2 ACT wires in order to make them long enough to reach the air box. Solder the wire extensions on the existing wires & use heat shrink tubing to cover the splices. Offset the place where you cut the wires so that you don't have a big bulge when you put heat shrink over the 2 wires to cover & protect them. The air box gets a hole (5/8" or so) for the ACT drilled about 1 1/4" down & 1/1/4" in on the front top side near the upper radiator hose. A brass fitting nut from Home Depot or Ace Hardware secures the ACT into the air box.

If you are very clever, you will find that the ACT connector comes apart so that you can remove the pins. A very small screwdriver releases the lock in the front of the center insert, while another small screwdriver inserted in the back pushes it out. Once the center insert is out of the connector shell, the pins come out easily. New pins are available from AutoZone in a $5 electrical pin kit for Fords. Crimping the pins on the extender wires saves you from having to splice them twice: once to put the connector on and once to extend the wires.

6 ft black 18 gauge wire
6 ft green 18 gauge wire
6 ft 1/4" heat shrink tubing
1 ft 3/16" heat shrink tubing

Measure the 2 extender wires & cut them to length, crimp one set of pins on them. Then mate up the extender pins with the wiring harness & slide the 3/16" heat shrink tubing over them & shrink the tubing. Then slide the 1/4" heat shrink tubing over the pair of wires and shrink the tubing. When you are done you'll have about 1" of wire left without heat shrink tubing on it to strip & crimp the new pins on. Stick the new pins in the old connector shell, assemble it and you are done. It looks as good as factory. Some wire loom can be used to enhance the "Factory Look".

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Underhoodpictures003.jpg


Use the TPS and IAB from your old throttle body. All the EGR passages were there and fit OK. Use you old fuel rails and regulator. You will probably need a new EGR spacer adapter and gaskets. Without the EGR spacer, there is no place to mount the throttle linkage support bracket.

I used the stock water lines on the Explorer manifold and they connected up to the EGR without any problems. I made a “U” out of ½” copper pipe and sweat soldered it together. Then I used it and some hose with clamps to bypass the leaky heater.

The vacuum lines you need are 1 small line for fuel pressure regulator, 1 small line for A/C,1 small line for EGR and another small line for the smog pump. One big line at the back goes to the vacuum tree for the power brake & A/C, one big line goes to the PVC valve. The other big line goes out the front for the carbon canister. In a pinch, one of the small lines can connect to the spare port on the vacuum tree. Cap or plug the remaining lines since they aren't needed.

The stock Explorer linkage didn't come anywhere near fitting, so I made an adapter plate for the throttle linkage so I could use the 65 MM throttle body.

This is what I did:
Make a drawing of the position of the old throttle body linkage arm and its angular position relative to the centerline of the throttle body. Remove the ball stud off the explorer TB to make way for the adapter plate. Drill and tap a 10-32 hole in the linkage parallel to the TB shaft. Make an angle bracket out of 1" angle iron 3/8", drill a 3/16” hole in the center of each one of the legs. Then bolt it on where the hole was drilled & tapped. Then make a circular adapter plate out of 1/4" thick aluminum to bolt the two linkage arms together. Then bolt the aluminum plate to the existing linkage, and the angle bracket. Next mount the arm with the ball stud off the old throttle body on the adapter plate using the drawing to get the angle correct. You will need an aircraft type countersink for one of the bolts that secures the plate to the explorer linkage arm. It ends up being under the arm with the ball stud for the linkage. It works great and looks neat.

The Explorer TB could have been real simple if I had a gas welding torch or taken the TB to a welding shop. Just grind the mushroomed part of the TB shafts so that you can pry the linkage arms off. Then swap the stock arm onto the Explorer TB and braze it onto the shaft. It Takes about 3 minutes or less worth of work with the torch, so it shouldn't cost much.

I didn't have access to a welder, so I fabb'ed the plate in my shop. I took about 1.5 hours to do it, it was a measure, cut, and fit type of operation.

Also see http://www.veryuseful.com/mustang/tech/engine/ConvertingExplorer65mmTB.pdf for modifications to adapt the 65 MM Explorer TB to a Mustang

Vacuum line connections:
One large vacuum line from the upper front goes to the carbon canister

One large vacuum line from the rear goes to the vacuum tree.

One small line in the front feeds the Smog pump solenoid control valves on the rear of the passenger side wheel well..

One small line in the rear goes to the fuel pressure regulator.

One small line in the rear goes to the EGR suction regulator.

One large line in the rear goes to the PVC valve.

Diagram courtesy of Tmoss & Stang&2birds - Typical Vacuum Routing for a Fox stang 5.0:
mustangFoxFordVacuumDiagram.jpg
 
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A little trick we always employ... Get an adjustable timing chain and retard the cam a few degrees. It will give you a bit more up top using a stock cam. I don't believe you will see more power, but it will move the power and up a little.
 
alot of those questions sould've been answered in the research you did beofre deciding to make this swap
Some were answered, but not all, so I am asking for anything I might have overlooked and things that will make the swap easier. I know others have done the same swap and have learned from it, if I can take advantage of their knowledge and make my engine swap easier I would appreciate it.
 
The 96 Explorer EGR works the same as the 86-93 Fox 5.0 Mustangs.
The Explorer intake manifold vacuum routing is a little different, but not difficult to manage. The Explorer intake swap tech note below will help you get things working..


Thanks for the info, I already have a 65mm TB-Spacer on my stock intake, and I plan on using it and will probably just have the Explorer lower drilled and tapped, I have everything needed to get it drilled and tapped properly but I had not heard of using the airbox before, I had heard of others that had mounted the ACT in the elbow before the TB but that looked like it might cut down air flow to the TB while the way you mounted it wouldn't . The diagram will help me get the Vac. lines routed properly, Thanks! When you did the change did you change the cam to a HO cam or a a different cam? What kind of power difference did you notice, I know a lot of people have done the swap on paper but would rather hear from someone that has actually done it on their own car. I know I have to put in the oil filter adapter and NPD has them for only $6, I plan on getting a new oil pump also, what I am unsure of is the shaft that drives the pump, is it the same in the Explorer or should I use the one from my old engine? The motor that is in my car now was bought off Craigslist after my OE crank broke and destroyed the block, I put in new timing gears and chain on it before putting it in and it only has about 6,000 miles on it since then so I plan on using those on the Explorer motor.
I was looking at getting an E303 cam or TFS stage 1 but they say to go with a higher stall torque converter and others have said to just install the HO cam and go with 1.7 roller rockers so I am planning on the stock HO cam and installing rockers later when I have the cash for them. I am trying to stay inexpensive but don't want to be cheap and cost myself more money later on. I am the original owner of the car, it's a 90 GT with an AOD and 3.73 gears, but I might swap those out for another set I have which are 3.27's so I don't run out of 1st and 2nd gear so fast.
 
I'd use a different cam. If you are upgrading everything else why not do the cam since you are there. Then you can actually use the upgrades to the full potential
I thought about changing the cam but the E303 and TFS stage 1 both say to go with a higher stall torque convertor, I don't have the cash right now for both cam and convertor. I'm not racing the car, I'm in my 50's and just want a nice DD. Mostly changing the motor because the one in the car now I bought off Craigslist after my OE crank broke and it started smoking a bit last Fall.
 
Which is not ideal on a street car or daily driver

What I suggested is not ideal in a street car or daily driver?

Moving the power and up I don't think is going to negatively affect the feel on the street. At least I never noticed it with the cars we have done it on. I prefer having more room up top, where you end up when your foots down. I would do this over an aftermarket mild cam any day of the week!
 
What I suggested is not ideal in a street car or daily driver?

Moving the power and up I don't think is going to negatively affect the feel on the street. At least I never noticed it with the cars we have done it on. I prefer having more room up top, where you end up when your foots down. I would do this over an aftermarket mild cam any day of the week!

That works very well with a manual shift and 3.55 or greater rear gears. Not a great plan with an AOD wit a stock torque converter and 2.73 rear gears. You have to be moving very fast in order to get the engine RPMs up into the power band where it pulls good. That translates into difficulty in getting past slow farmers in beat up old pickup trucks or little old gray haired ladies pushing their grocery cart Honda to the supermarket.:)
 
I must have missed that this is a 2.73 geared AOD car, in which case moving the power and up might not be the best bet. Mobil website on my phone doesn't allow me to see signatures, so I plead ignorance :D.

I have 3.73 gears in my car but it is an AOD with a stock convertor, I also run 265/50r15's on the back which are a little shorter than the OE 225/60r15's. I am thinking about swapping out the 3.73's for a set of 3.27's because the car comes out of 1st gear at about 15-20mph. I'll find out how it runs after I get the motor swap done and decide if I want to change the gears.
 
Fox auto by willis has a bunch of exploders and mustangs and tbirds. plenty of 5.0 parts to go through. i just got a set of gt40 heads from them off a exploder. had them ported and new valves from Tom through Performance in Adrian. he is learning and doing it all on the side so his prices are great. I kept the mustang intakes due to hieght concerns and not wanting a cowl hood(that dream failed) and had Tom port match everything including shortys. I put a crane .510 lift cam in mine and had it bored .40 also from Tom. machine and port work was $500. i did the rest of the work myself over the winter. I have a T5 in my 90' and 4.10 for now. headed to milan May 7th for test n tune to see how it goes.
 
I found an explorer motor and have it stripped down, I already installed my old cam and have a set of TFS springs ready to go after I get the heads cleaned. I'm keeping mine closer to stock so it can be a daily driver that I can drive anywhere. Once I get some time off work I'll start working on it more but I've been working 10 hr days, most Saturdays and a few Sundays.............just not enough time to get to it now.