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Hello, I have been searching around and cant find a clear cut answer. I blew up my 2001 XJR and am in the market for a replacement engine. I found several options on car-part.com however.
My question is, what are the differences between the two different EngineID ranges?
This is the option I would like to purchase, but they are telling me the different engine ID's are non-interchangable:
They have suggested this one, which is from a 2003:
I don't understand how a 2002 motor will not work, but a 2003 will.
ANY 2000 to 2003 AJ27 Supercharged complete engine will bolt in and 'plug-up' to your car without modification.(this includes 4.0 XKR engines)
The later engines with the silent running chains will not have some internal parts that match if you try to combine things like chains, upper oil sump, oil pump etc.
As long as the engines are SUPERCHARGED 4.0 AJ27. Look for CMPS on BOTH heads. The AJ26 will only have ONE CMPS and it will be located on the left head.
The AJ26 throttle assy will have a vacuum actuator and the AJ27 DOES NOT.
The earlier 1998/99 AJ26 engines are not a direct fit (not 'plug-and-play').
The AJ26 will require modification but can work with some effort.
Last edited by motorcarman; 02-17-2021 at 02:26 PM.
The earlier 1998/99 AJ26 engines are not a direct fit (not 'plug-and-play').
The AJ26 will require modification but can work with some effort.
Ok, just to make sure I’ve properly beat this horse to death, the first motor listed above (JJ1390 - 58k miles) is what I will be purchasing, that is an appropriate AJ27 engine, correct?
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The JJ1390 (58k miles) is from a 2002 Jaguar XK8
The JJ1728 (84k miles) is from a 2003 Jaguar XJR
If anything, it would stand to reason the 2002 would be a closer match to my 2001. Right?
From the description, BOTH will be compatible.
The 2002 will 'likely' have the silent running Morse style primaries with the updated tensioners/guides, but the 2003 will most certainly have these.
Might want to 'pop' a cam cover just to be sure it all looks good.
All electrical connectors will be compatible with your car. (try to get the engine complete with harness)
Ok cool. Unfortunately, I do not have access to either engine prior to purchasing.
The seller (M and M Auto Parts, Inc) is adamant that JJ1390 will not work for my car, but I know they are just reading that info from whatever system they use.
hahahaha oh man don’t get me started on that. I bought an Ls for it and went back and forth for months. I ended up not wanting to put $12k into this car, so this motor it is.
Good god. After much back and forth it was determined the motor with 54k miles wasn't even there. I found another one, at a different shop, and just purchased. It has higher miles than I would have liked, but the price was right and Im just tired of messing with this car.
Here is a link to my build thread, where I will continue updates.
02-17-2021, 01:28 PM
X308 Engine Differences by Year?
