2004 w/ Jaguar 4.2 Engine Swap | Page 2 | Ford Thunderbird forum club group 1955-2005 models
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2004 w/ Jaguar 4.2 Engine Swap

Will the 4.2 engine have sufficient free space to rock the maximum amount on its rubber engine mounts during engine torque swings?
Are the Jag heads wider than the Ford? The Ford 3.9 is already a tight fit. The WIKI on the AJ engines says this about the 3.9:

"The 3.9 L (3,934 cc) AJ30/AJ35 variant is a unique displacement used only by Ford and Lincoln and is built in Ford's Lima, OH engine plant. Bore and stroke is 86 mm × 85 mm (3.39 in × 3.35 in). The AJ35 version introduced for the 2003 model year added variable valve timing of the intake camshafts and electronic throttle control. While the block, crankshaft, pistons, and connecting rods are all unique to this displacement, many other parts are shared with the AJ-V8 engines produced in the UK by Jaguar." Heads are not mentioned as being unique to the LS and Thunderbird applications. Just wondering.

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What an exciting project! Interesting to me is that even though the engines are essentially identical, I think the transmissions are different: the Thunderbird has a five speed and the Jaguar has a ZF six speed. I guess the rationale is that once they upgraded the Thunderbirds in 2003 to the variable valve timing that the Jags already had, the Jags had little left to justify their 25% higher price. The extra 200cc displacement in the regular Jag 4.2 adds only about 20 horsepower. So they gave the Jag a better, six speed, transmission. But the R model supercharger adds another 120 horsepower over the Tbird, and boy will you be spinning those tires!!!
 
What an exciting project! Interesting to me is that even though the engines are essentially identical, I think the transmissions are different: the Thunderbird has a five speed and the Jaguar has a ZF six speed. I guess the rationale is that once they upgraded the Thunderbirds in 2003 to the variable valve timing that the Jags already had, the Jags had little left to justify their 25% higher price. The extra 200cc displacement in the regular Jag 4.2 adds only about 20 horsepower. So they gave the Jag a better, six speed, transmission. But the R model supercharger adds another 120 horsepower over the Tbird, and boy will you be spinning those tires!!!
Ok, from what I'm reading, do you mean that a Jag ZF six speed would fit on a TBird? Would it fit on a 2002 with the 3.9. I do mostly highway driving and could sure use an extra lower gear for cruising.
 
Ok, from what I'm reading, do you mean that a Jag ZF six speed would fit on a TBird? Would it fit on a 2002 with the 3.9. I do mostly highway driving and could sure use an extra lower gear for cruising.
Unfortunately I don't know anyone who has tried this, so I don't know if it will fit. I would assume the tunnels are very similar and obviously the linkages should swap. The big question is whether the Ford computers could be reprogrammed or if you'd need to swap in Jag computers.
 
I subscribed to get updates on this. I'm looking forward to hearing how all the ECM issues get resolved - that's the real bugaboo here. If your mechanic is able to get all this sorted out, well, I'm guessing he might end up with a line of T-Bird owners at his door trying to throw money at him. (Of course, he may never want to see another one after this. . .)
I think the ZF box would be a significant upgrade, and why not, in for a penny, in for a pound.
Good luck with the project.
 
Unfortunately I don't know anyone who has tried this, so I don't know if it will fit. I would assume the tunnels are very similar and obviously the linkages should swap. The big question is whether the Ford computers could be reprogrammed or if you'd need to swap in Jag computers.
One way or another, the computer issue will be the knot of the job.
 
We're close everybody! The re-flashed ECM is in. Tomorrow he'll start going back together and install the PowerStop brake kit. After that, we should be good to hit the streets! So happy to finally be close to having it back. It's been dead for well over a year.

I am worried about the factory driveshaft. I feel like i've read somewhere about these breaking when people remove the factory speed limiter. I'm concerned the extra torque could cause some real damage. Does anyone know if there's a company that makes an aluminum driveshaft? Or will I need to have one fabricated?

I'm looking forward to posting photos of the finished project, and maybe link a video of those tires spinning as well. Cheers!

I subscribed to get updates on this. I'm looking forward to hearing how all the ECM issues get resolved - that's the real bugaboo here. If your mechanic is able to get all this sorted out, well, I'm guessing he might end up with a line of T-Bird owners at his door trying to throw money at him. (Of course, he may never want to see another one after this. . .)
I think the ZF box would be a significant upgrade, and why not, in for a penny, in for a pound.
Good luck with the project.
I think the latter is closer to the truth. With the amount of time it took I'm sure he's done with them.

I'll definitely be looking into the ZF box in the future. I'm not sure if they offered it in the US but I do believe they had a manual S Type R. Who knows, might see an actual manual swap one of these days.
 
There are any number of places that can make a custom heavy duty driveshaft for you. Now, an aluminum one - that might be tougher to source.

In any case, I'm looking forward to the photos.
 
It's been a while..

Long story short, the car is out of the shop, but nowhere near done.
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I think the mechanic just bit off more than he could chew. Things weren't adding up and it kept getting pushed back all year so I've got it back to see what I can accomplish with the help of some much more knowledgeable friends. No hate to the mechanic, but I was not impressed with the condition of the 4.2l engine he installed. I've gone through and done valve cover gaskets, plugs, wires, remanufactured injectors, and replaced the coolant pipes that run underneath the supercharger. I've got the supercharger assembly, and what seems to be most of the coolant system, but everything else is a mess or just missing. And all the bolts for everything were just thrown in the cab!!! Multiple gallon bags of bolts that I've got to sort out!


Being negative isn't going to get it running though. My main issue I'm trying to work through is the wiring situation. I don't think I should go up with the supercharger assembly until the wiring harness is figured out and routed. I've got both the STR harness and the TBird harness. Most all of the connectors are different. My friend went through the wiring diagrams while it was still in the shop, and said other than a few parts the stock Ford ECU should be able to run everything but I can't wrap my head around that. If anyone has ANY advice on where I need to start with wiring please reach out. I've heard about one or two people who have done this swap before so if anyone has I would love to pick their brains. I'll add some more photos if anyone is curious of what I'm working with. All comments are welcome.

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I think the mechanic just bit off more than he could chew.
What made them think they could even do the job in the first place? I don't even recall anyone on our forums since 2002 doing anything this extensive.
I've heard about one or two people who have done this swap before so if anyone has I would love to pick their brains. I'll add some more photos if anyone is curious of what I'm working with. All comments are welcome.
They weren't here or on any other related forums. It's been discussed here as far back as 2006 and one of the guys at the Ford plant said "I spoke with an Engineer from the Lima Engine Plant where the engines were to be built. He said the Jaguar uses a Denso control box (computer) while the Thunderbird uses a "Black Oak" box. he said they spent "HUGE" amounts of time to get the Denso box to talk to the Black Oak box. The Blown Bird was to use the Denzo box to control the engine while the Black Oak box would control the Traction Control, several sensors, the drive-by-wire systems, etc. " You will note when you posted on the jag forums, the person said the same concern about the computers.

Also, an explanation here- https://forums.fordthunderbirdforum.com/threads/adding-a-supercharger-to-a-2003.5589/post-34038

If you get the car running, I will be amazed. Anyone who has successfully done this would have probably done it in a high-end custom shop, like the ones you see on television!

This has been done on the Lincoln LS and the shop that did it has several videos, so it may help get you in the right direction. As you can see from his posts over 1+ year, it's not straight forward at all.


Discussed swapping with a remanufactured engine or a coyote but the Jaguar engine was by far the quickest/cheapest option. $3,652 for the swap and $1,096 for the brake kit.
This turned out to be untrue. The mechanic better be glad I'm not the customer, I'd 100% file a law suit. It's one thing to swap engines on cars like Mustang, but trying to swap out a Jaguar Engine from 20 years ago when pretty much nobody has done it is completely asinine, especially for 3600 bucks. No rational thinking business would have even suggested doing this.

FYI Ford Purchased Jaguar in 1989 and sold it in 2008. This whole mess with Jaguar was a very short stint with the engines in the Tbird & Lincoln LS.
 
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There are engine mounts and a few other parts to swap a GM LS motor into these (Lincoln LS). See Stu Kelly Racing (sic?). Most DIYer's are going to adapt a compatible GM donor instrument cluster, into the existing space instead of trying to re-pin a hundred wires- sometimes these can look better than you think. Still, there is tons of work to get to a point of being called "well sorted". Bottom line is that you never want to be the first one attempting any swap. Maybe someday, a place like Stu Kelly will offer something akin to a swap kit. I had an LS swapped RX7 convertible that was beautifully done. It was a lot easier because all of the swap parts were developed, proven AND for sale. Not enough available for our cars as of now to swap and stay sane.
 

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it’s already been done. this is a gen 1 cable throttle car that needs even more work to do, adapting the throttle is the only real challenge. everything else is mix and match zero fab work


 
I love this forum so I thought I’d add to it myself. My 04 Thunderbird engine blew on me a few months ago and right now it’s in the shop getting a 4.2 Jaguar Supercharged engine installed as well as a PowerStop brake kit. I’ve seen multiple discussions about swapping a 4.2l in but haven’t seen any done. Any questions or advice is welcome. I’ll try to update this as the project moves along!
How did it go? Cost?
 
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