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4.6 DOHC in a F 150 or Expy, 4X4?

I'm about to make the swap of a '93 Mark VIII engine into my '98 Expedition 4X4. The research I've done makes me believe it should not be too much of a problem. The major concerns are the ECM and the exhaust, especially the driver side exhaust, the Mark VIII has the Cat. welded directly to the manifold and there may be some interference with other chassis or drivetrain components. If there is I hope to get around this problem by using the left side exhaust manifold from a Mustang Mach 1 that is the same as a Cobra.
The ECM is a guessing game but I believe the Expedition unit will work properly as the same swap has been done in many V8 Mustangs and T-Birds. The pin count and arrangement of the Expedition are the same as the '96 Mark VIII. The only problem I can see so far is that several of the sensors may have to have the connecting wires cut and spliced as well as using the basic engine wire harness from a '96 Mark VIII as the connector pins changed from a large diameter on the OBD I system to a much smaller diameter in the OBD II system. I also intend to use an electric fan for the cooling system instead of that big clunky OEM fan and that way there may be enough room for a turbocharger.
After the bolt in procedure the Expedition will go to the muffler shop for pipe fabrication.
Another feature of the '96 Mark VIII engine is that it uses the same coil packs as that used on my Expedition
I will post the results with pics when the truck is driveable

Any info would be greatly appreciated.
 

Skandocious

Post Whores Make Me Sick
19,076
655
California
I think you might run into problems if you try to recycle the Expedition computer... Those are two drastically different vehicles and I can imagine that they have wildly different computer controls. And how about the transmissions? Are they the same? The computer is what controls those transmissions. Generally speaking-- you want to use the computer from the engine/trans that you're using for the swap; or at least thats the general rule when doing engine swaps on older vehicles like mine.

Welcome to FTF :wavey:
 
is the Mark engine stock or modified?? one thing to think of is that motor was geared and set up for a vehicle that is way lighter than the expy....a 4.6 from a car is a lot different than a truck 4.6....just a thought


and yes welcome to FTF
 
973
11
better off NOT doing that.. this is why on trucks you see "Triton".. the triton motors are the ones designed for trucks/heavy vehicles... i believe they use the triton in the CVPI
 
Thanks for the feedback gents, I'm still doing my research on this project and I'm looking for some H.P. and Torque comparisons.
Thanks especially to Klatt 89 for the links. So far the more I look the more I think it would be a successful project with really good results. At this time a turbo is almost a certainty, I have 2 of the size for 5.0 Mustangs an 1 from a Cat powered IHC scraper that was once used on a 265 cid Chevvy with powerglide and it worked really well many years ago. There looks like there's plenty of room for the big one.
 

klatt_89

Gotta Be Somebody
Your welcome, glad to help you out. I like the DOHC motors myself. Course I also have a brand new 4.6 DOHC sitting in my storage :D Never ran before....but that's a build up project.
 
973
11
is the Mark engine stock or modified?? one thing to think of is that motor was geared and set up for a vehicle that is way lighter than the expy....a 4.6 from a car is a lot different than a truck 4.6....just a thought


and yes welcome to FTF


Off topic, but its funny, your from Woodbury TN.. my last name is Woodbury lol
 
is the Mark engine stock or modified?? one thing to think of is that motor was geared and set up for a vehicle that is way lighter than the expy....a 4.6 from a car is a lot different than a truck 4.6....just a thought


and yes welcome to FTF

The DOHC engine is stock right now and will likely stay that way except for a turbo and if needed some NOS. Back in the '70s I did a turbo on a 427 mustang and then added NOS to make up for the the turbo lag. I would like to purt a 427 SOHC in it, but I sold the ones I had a long time ago.
My son has a Mustang Cobra and it puts out a healthy amount of power opn the dyno and there are a lot of the stock 4.6s putting out over 800 HP with blowers and spray. I won't need anywhere that much power but not long ago too much power was almost enough.
 
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I would love to have a 427 SOHC engine, i'm sure you'll have fun with the DOHC.

but that's like everyone's dream... :p

I have a 4.6L SOHC in my mustang, but I wish I had the 32v and the ram air intake from the Mach1. ;)

Best threads ever tonight, I swear.... :rofl: :beer: smilienothingFunnyto
 
You have a good point there! Ya could make your stang have a DOHC :D

Thats what I like about the Mark VIII:

32v V8, they look cool, MN12 chassis, independent rear axle, luxurious... etc.

My mustang looks cooler though... YelloThumbUp :D
 

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