Cylinder Head Number

I have a Jaguar 3.8L engine, and was hoping that someone could help me out with the engine numbers. Here’s the numbers that I have and their location:
R8650-8 On the block, at the oil pump
AK466 On the rear of the block
HX186 Rear of the cylinder head
KJ7064-8 Front of the cylinder head

Any information that you could send my way would be greatly appreciated!!

Dave R

Off the top of my head, it is from an E-type, it was probably built sometime in the early months of 1963 and has lower compression pistons (-8 as opposed to -9) and was supplied to a country with lower octane ratings. (US engines were 1:9 compression ratio). The head has been changed as the original numbers should be the same for the block (at the oil pump) and for the head (at the front of the valley). I’m not sure when they went from an R to an RA prefix, but it was after early December, 1962 and before July 1963.
I don’t know anything about the other numbers.
What are your plans for the engine?

A KJxxxx head is off a 3.4 Mk2, so not a straight port E Type head.

The other 2 numbers are foundry casting numbers. There should be a round reverse imprint with a date of block manufacture, front right low down probably.

If you have a flywheel this should have a number stamped on the rim to identify the engine it belongs to.

Hi Ed, I originally bought this package to build a hot rod. The Jag 6 is one of the coolest looking engines I’ve ever seen. I got it from a guy who disassembled a car and lost interest. Car was long gone when I got there. Its a nice complete package, engine, manual gearbox with overdrive, mounts, flywheel, starter, generator, fan etc. I’ll probably sell it so it can go back in a Jag now. I need to figure out how to identify the trans. Thank you for sharing info.

Hi Andrew, did Jag use that cylinder head on any 3.8 Engines? Thank you