How to: '02 limited 4.0 to 4.6 dohc swap

All of the dohc valve covers will interchange. I just bought a set off of eBay for a navigator. I have an extra set of coil covers I can send you if you don't have any. They are painted gunmetal, but that's not a big deal.

Navigator valve covers

I thought the Navigator valve covers might work but didn't know for sure since they have a different Ford part number. I'll watch for a pair on eBay.
The ones below are listed for a 1999 & 2000 Navigator.


I can't tell if they are the same as yours. Do I need to look for 2001 or later years?
Edit: are all of the DOHC valve covers metal?

Yes they are all metal. The pcv/breather hole locations are different on the ones in the pic. Mine are both on the back of the cover. I just remembered that mine are off of a mark VIII not a navigator. I paid $100 for the set shipped, with the coil covers. But they will physically interchange with all of the dohc heads. It didn't really matter to me where the pcv hole was since I had to make all of the hoses anyway.

Can't find just engines in my neck of the woods. Cheapest aviator with a bad trans is 1700, 180k on engine. I like the idea of the 5.4 though. Only Navigators available for cheap are 97-2000. The spark plug wasn't fixed until 02 or 03 I believe. First have to find a 02-05 with a bad V8 for cheap to play with. Maybe Coparts auto auction for an engine.

I have a friend who lives in Woodstock, GA. It's a nice little place. He works at Proline Racing.

Mark VIII COP

According to Rock Auto listings the Mark VIII had COP in 1997 & 1998.
Do the ones in this listing look suitable: 1998 Lincoln Mark VIII SVT Cobra DOHC 4.6L COP SWAP valve covers?
The following is in the text: "I also have the power steering bracket and a set of coils available for an additional 50.00. The power steering bracket will get rid of the big bracket to get a cleaner engine bay." Is this bracket worth buying?

I think that is the same guy I bought my valve covers from. Not sure what he means by power steering bracket. I used the fluid reservoir and bracket from the explorer and the pump from the mark viii. $50 for the coils is probably worth it though. Even if you have to replace a couple. They can get expensive

Egr?

87350gta said:

. . . I had to delete egr so my check engine light is constantly on. . .

Click to expand...

Why did you have to delete EGR? I'm trying to determine if I can install a system using the Aviator components but don't have the EGR valve and the EGR tube is mangled/cut off. I'm going to a salvage yard this morning for Aviator valve covers and exhaust manifolds. I'm trying to decide if I should also purchase the EGR valve and EGR tube.

It was only deleted because of the intake I used. If you use an aviator intake, you will be fine to use egr. I plan on switching to the later mark VIII or cobra intake at some point and reinstalling egr.

EGR advice

Thanks for the advice! Unfortunately, the salvage yard did not have the EGR tube and it is no longer available from Ford. I'll start searching for new old stock from dealers and supply houses. I purchased the exhaust manifolds and valve covers. There is only one large diameter washer/bushing on the covers. Do I need these washers/bushings for the COP?

They are just seals, they come in the new valve cover gasket set. Felpro has a set with everything you need. I just confirmed with my parts department, ford no longer makes that tube, and no dealers stock it. So it's either aftermarket, salvage yard, or ebay.

custom EGR system

It's a good thing nobody has the Aviator EGR tube because I may not be able to use one anyway. I'm going to be using the 2002 PCM which supports an EGR system using an EGR valve that controls flow.

And a DPFE sensor that measures the differential pressure between two orifices in the EGR tube.


The Aviator uses an EGR valve with a valve displacement sensor.

Unless the Aviator valve displacement sensor output signal is comparable to the DPFE sensor output signal I won't be able to use the Aviator EGR valve.

I would definitely try and use the explorer setup. It is better. What pcm are you going to use? Also, what chassis are you going to put this in? I think I missed that in the post.

2002 or 2003

I'll be using a 2002 or 2003 Explorer chassis and the PCM that comes with the vehicle. I'd like to find one with blown head gaskets. My second choice would be one with a bad transmission since it will need to be upgraded for the greater power. I'll be generating some EGR system design posts soon in my swap thread: Next project vehicle?

Imrc?

Do you have the IMRC working yet?

I do not. I bought an rpm switch to control them, then when I went to install it, I discovered that there is no rpm signal. So I need to order a tach adapter to run my rpm switch.

tach signal

That's about as far a I got when I was going to install VIS on my Sport. I purchased an MSD RPM activated switch and a 3000 rpm chip to plug into it. See the following thread for some advice from snoranger: VIS Conversion

more harness details

87350gta said:

. . . I remade the v8 explorer harness and grafted in a dohc navigator harness I have. . .

Click to expand...

It looks like there may be three engine wiring harnesses on the Mach 1. One is the injector wiring harness. The second is the PCM wiring harness. And the last is the starter motor wiring harness. I suspect the Aviator wiring is similar. How do these differ from the Explorer wiring harness? What part of the Navigator harness did you use? I can purchase a Navigator injector harness for about $75 but a Mach 1 harness is about $200 more. I did extensive rewiring of my Sport harness when I added the M90 and don't mind doing the same for the DOHC to save money.

I used the navigator coil wiring harness, and spliced it into the explorer injector harness. There is also a separate "power" harness that runs to the alternator and battery. I didn't have to change it at all. I basically used the complete explorer engine harness and cut off the wires to the coils and spliced on the navigator wiring. You have to watch the coil wires. The dohc coils are wired backwards from the sohc coils.

COP wiring

That doesn't sound like much work. I'll do the same. I'll probably replace the injector connectors if they're like the ones that were on my Sport. They are difficult to remove and break easily so they don't make a reliable connection. These are what I replaced them with.