I have almost completed the engine swap project. The motor in in and running. Just have a vacuum leak to run down tomorrow. I do have a lot of motor parts left over. If anyone needs any of them, they may have them. Just let me know what you what you want and I will look. Thanks for all the great info on this forum. I never would have tried it with out all you folks helping. steve in cape coral.

 

Did you drop the 4.2 in whole or did you swap in only the bottom of the engine and keep the 4.0 heads and injection?

 

I used the 4.0 fuel rails with injectors, the bottom sub sump. the cams, the timing gears and chains and the supercharger. The rest was 4.2 including block and heads.

 

Why did you do the swap? What difficulties did you run into?

Is it possible to swap in a 4.2 supercharged engine with a 4.0 xkr merc box on a 4.0 Xk8?

 

I did the swap because the 4.0 motor was toast. There was a lot of medal in the oil pan and no compression. The 4.2 motor has a lot of improvements and made sense to change. There are several post on this site about doing this. There are some things I ran into that took a little redoing, but most of it is covered by the post. I don't know about the swap on a XK8.

 

If you have plenty of funds, time, and don't give up easily, it might be possible. The usual answer is... buy a factory XKR

 

I have none of those, I was just wondering. I wasn't aware it is possible to go from a 4.0 to a 4.2...

That being said, I was under the impression that the 4.2 engine is actually slightly less powerful than the 4.0. Could anyone confirm if that's true?

 

Not true

 

What are the HP numbers?

I thought the 4.0 NA is 290 HP at 290 lb-ft of torque and the supercharged 4.0 is about 380 HP and lb-ft of torque, give or take. However, I'm not aware what the numbers are for the 4.2 engines.

 

Jaguar AJ-V8 engine - Wikipedia, the free encyclopedia it's all in there

 

Just to let you know, I have to date spent $1676 including motor, freight, gaskets, bolts degreaser, timing tool set, oil pickup tube serpentine belt, oil and filter. Still have to get antifreeze. The motor produces a lot more hp than my stock 2003 Xk8. All the info to do the job was found on this forum and on the internet. I did this swap in my garage at home and I am not a professional mechanic, just a hobbyist. I would love to buy a new xkr, but anybody with money can do that. My way has real satisfaction in knowing I am keeping another of these fine cars from the scrapper. steve

 

Stevee
Your Care package arrived today.
Thank you
Let me know how I may help.
JM