Which year is this engine number from (relatove to change in manual gearbox ratio)

XJ
1

I am trying to figure out which year engine number 8L22647 would have been from

The relevance is this is the engine number after which the manual gearbox first gear ratio changed from 2.933 to 3.238

2

Hi Russell,

You could try xj6data.com but I have an engine number in that sort of range (can’t remember number exactly) and there was no joy in my case, but good luck,

Bob

3

I’m surprised that a change to the gearbox is referenced to a specific engine number; would have thought gearbox number would be more relevant. Engine 8L70840 is from 1978, very late Series 2, and S1’s are prefixed 7L, so my guess would be early to mid Series 2 production, say '74 to '76. If that data is from the factory parts manual, and you are looking for parts for a particular gearbox, it’s not terribly helpful if you don’t have the original engine.

4

Yes - it seemed odd to me too. That clue came from googling the part numbers for the 3.238 first gear and cluster. The parts suppliers indicated that the parts were 3.4 xj6, 4.2 after that engine number and XJ-S

Nigel Thorley refers to the change, but doesn’t specify. One could infer that it was sometime after May 1975

5

Looks like it. That was the time both the 3.4 and XJS appeared, so sometime mid 75 would seem correct.

6

Thorley gives a clue - 8L26204 was May 1976, so 8L22647 (different source) would be 4000 engine units (perhaps 6 months?) earlier