Another local 150 DHC owner has a replacement cyl head with J2560-8 number. Could anyone shed any light on this. What is this head from? or is it a factory replacement? his Chassis number is S 837437 and his original head number was V1414-8 .Its a May 1958 car, but what is also rather strange is that his engine number should be in the 3100 to 4000 range, and there is only one other car listed on XKData as a LHD DHC with a V-1408 engine and that’s an Aug 1957 car,S 837007.
I’m not aware of any XK 6 cylinder engine with a “J” prefix.
Here is the list:
http://www.jag-lovers.org/xk-lovers/library/engine_numbers.htm
At the risk of sounding silly - Could the 'J" just be a mis-stamped ‘V’ ?
Got a photo?
Prefixes BJ and KJ were used in the latter part of the '60s in Mark 2s. Could somebody have neglected to stamp the B or K?
Get the number stamped at the rear if you can; it may tell us what year and possibly month it was made.
Also with a mirror try to see the raised casting numbers on the underside, to be sure which type head this is.
Our general belief is that factory replacement heads were not stamped at all. I have such a head from the mid '50s, and I believe one or two others on this forum own or have seen others.
As to his original number being outside of the normal expected range, first there was no serious attempt by the factory to keep engines in sequential order, and second this engine may have initially failed inspection and gone around for rework before being placed back in the stock queue.
Thanks for all input, I shall get the owner to do more detailed inspection .A very light stamping of a V could very look like a J.
Rob the rework of an engine is a very viable reason as to the low orig engine number in the midst of much higher ones.