I just purchased my project XK8. The engine has been torn down by the previous owner and I am hesitant to rebuild the motor without knowing if everything is there. I also have a 1997 lincoln mark viii that I was going to use as a donor car for my 1967 mustang, however the mustang is far from being complete. Sooo i'm wondering if anyone has ever considered swaping the aj-v8 with a 4.6l dohc??

 

I own a 1993 Lincoln Mk VIII and also wondered why Ford didn't use the 4.6 in the Jag XKs.

It turns out that the width is about 2" too wide to fit in the (already tight) XK Engine Bay. Don't know about the height.

 

A little cutting and welding and it will fit just fine. ( little out of the box thinking!lol )

 

Well, a couple of major hurdles have to be overcome in order to make it all work.

First, the AJ-V8 engine has a completely different crank trigger mechanism. It fires at a different point on the wheel than a 4.6.

Second, the firing orders are different. Ours is 1-5-4-2-6-3-7-8. The 4.6 is 1-3-7-2-6-5-4-8. The jag computer cannot be reconfigured to match.

I have been trying to go the other way and stick the 4.2 in my 67 cougar, and holy crap, it is hell. Petrel can make the ECM to make it run, but that is about it. The sensors are on totally different calibration levels, and the values are different.

Now then, all that said, a little hope. If one were to remove all the wiring from the car, and knew the pin outs of the ford ecu, one could theoretically combine the two technologies and modify the jag harness system to allow the computer to accept the current values as correct. Adding resistors, etc.

I spent 3 hours on the phone with MSD trying to find a way to control the ignition and timing. If I could do that, I can fab a carbed intake and run it! Still working on it!

 

Try a mega-squirt.

 

+1

I guy I know runs one of these on his Camaro street rod and is upgrading it to a Lysolm twin screw setup. The EFI is very configurable and flexible.

Oh and here's the link:
MegaSquirt | Engine Management System | Electronic Fuel Injection - DIYAutoTune.com

Turns out, megasquirt . com is not family friendly.

 

It ain't like it used to be. Engine transplants are problematical and hardly worth the time, effort and money even if you are astute enough to understand and marry up all the interfaces.

Even back in the day when it was "simple" we used to take a donor engine with as much of the electrical harness and mechanical connections and misc do dads as we could lay hands on. Invariably, there would be the odd bracket or spring that had to be run down to complete the job.

I would attempt it on a modern engine only if it was an exact copy replacement/transplant.