Hello I have a 98 XJ8 VP making alot of engine noise. I havent torn into it yet to find the problem but been looking into replacing the engine. I found a 96 XJ6 VP with bad trans and am thinking of swapping to the 4.0 I6. My questions are
V8 and I6 trans interchangable?
Is this swap even worth the time?
I will have 2 complete running cars so should have all the necessities
Pros and cons of I6 vs V8

 

Oh forgot to mention. The XJ6 has some other minor parts that i can use like mainly the hood ornement lol mirrors sunroof windshield and other misc. I will either part out what is left of it or sell to a buddy to put his LT1 into and get most if not all my money back

 

The swap would be quite complicated. You'll have to swap wiring harnesses, computers, etc., at the very least.

 

I don't know if the XJ6 engine will bolt to your XJ8 transmission. You'll also need the XJ6 computer to run the six cylinder motor, but that computer may not properly manage the 8 cylinder transmission.

 

why looking for a downgrade and older engine?

 

Sounds like the perfect candidate for the the Chevy swap on another thread! I wouldn't bother trying to put a six where is doesn't belong

Chris

 

The wiring and computer swap will be easy. I am mainly concerned with the transmission bolting up and whether the I6 ecu will operate the V8 trans properly. Also want some pros and cons of both engines. The I6 is dime a dozen and the V8 seems pretty hard to find

 

Why put a chitty chevy pushrod at that were it doesnt belong? I would drop and might drop one of my Ford 4.6 DOHC Tekids motors in her.

 

Vince why is it a down grade? I did ask for pros and cons of both motors. Give me some usable infomation!

 

I am as big as a Ford guy as anyone! My first car that I purchased at the tender young age of 15 in California back in 1988 was a 1966 Mustang Fastback with a 289 4 speed. And have had a slew of desirable Fords that are worth some $$ now.

That being said, the Chevy motor is smaller than a comparable DOHC 4.6 and has the torque that this heavy car needs without revving the crap out of em and the company has the canbus to make it all work. Don't get me wrong, Im sure it can be done, but unless you have the $$, the kits seem like a no brainer to me. Heck, if my motor ever went south I would STRONGLY consider it.

Just my 2 cents

Chris

Pros, an inline 6 in just about any fashion, be it Ford, Chrysler, Chevy, Jag, BMW Mercedes etc are just bulletproof in nature.

Cons....it would probably take more effort than worth and you lose torque too.

 

Vince why is it a down grade? I did ask for pros and cons of both motors. Give me some usable infomation!

 

Chris I dont see putting a DOHC costing any more than a chevy. I dont know how don't know where you are with the DOHC but with just a few small tweeks that dont cost much you can be pushing 400hp with good torque. The only 2 things that bother me is the exhaust and fabbing engine mounts but both can be handled easily and cost efficient. Buth never mind all that right know. I am pulling the front off as I type to do a timing inspection
As far as the I6 these cars came with them 95 thru 97. Do you know the torque and hp rating? Havent had time to look it up yet. If I do an I6 i will have a complete 96 or 97 (obd2) for the swap. Thinkin of the I6 couse as you said they are bullet proof. Should get many years out of it. And they easy to find and cheap. Should have just found an XJ6 LMaO

 

The ECU has to communicate with all the other modules in the car. The X300 module will be totally lost.

 

The gearboxes are TOTALLY different!!!!!!!!!!!!
No they will NOT interchange.
To begin with the bolt patterns are different and the torque converters will not bolt up etc. etc. etc.

bob gauff

 

Thank you Bob thats what I was looking for. Not the answer I wanted tho. I guess its back to looking for a V8.

 

The LS swap kit includes everything needed to drop a LS in your Jag. You may have trouble with the 4.6L swap, as Jags have numerous computers that all need to communicate with each other. The LS swap kit has the pieces to make the LS motor communicate with the car. Last I heard, he was also working on a 6 speed GM manual tranny swap, as well. Search the forum. The info is there.

 

Thanks chad but will never put a chevy into anything lookin also at a 91 camaro for the 4.6 swap lol before i do any kind of swap like that i will get the lincoln ls motor or rebuild what i have

 

Not that the 4.6L isn't a good motor. A customer of ours is building a sweet street rod. A 1950 Mercury 4 door that he has grafted onto a 2009 AWD Mountaineer chassis, powered by the 4.6L motor. He plans on installing twin turbos in the exhaust for much added power. $20,000 was spent on custom made suspension pieces to make it sit just like a lead sled, while keeping the AWD intact. The entire Mountainer interior will be installed in the 1950 Merc body, down to the dash and factory Navigation system. He plans on getting a ton of horsepower out of the 4.6L motor, with no mods to the engine itself.

And the best part?

He's painting it Jaguar Racing Green, inspired by an X-Type he saw...

 

That sounds sweet i have done quite afew 4.6 transplants with mild tweeking you can get some really impressive numbers. My original plan with my xj8 was a 4.6 transplant but after some research i liked the 4.0 better makes good numbers and about 200 lbs lighter and i am sure i can boost the numbers with some effort. My goal was to just have a very nice driver. If i cant get this harmonic balancer bolt out and get this thing fixxed with in budget I am gonna off it and do another crown vic with the DOHC

 

You could always buy my 99 XJR. 370HP, oodles of torque, and the bulletproof Mercedes transmission. None of that VVT garbage, either. $4500 is my bottom dollar on it. There are guys on this forum that are pushing 650+ HP from the supercharged motor with bolt-on parts...