What year did Jaguar update the guides from plastic on the xj8 so they are no longer a primary issue? Thank you

 

05/01 I believe, but I couldn't tell you the engine number the change occurred at.

 

All AJV8 engines from 0108130000 onward have the improved timing system components from the factory.(engine date code NOT VIN or MY is the way to verify)

The MORSE style 'silent-running-chains' are paired with the new style guides.
The guides still have plastic runners, just a different design.

On the earlier engines I still use the original design guides but some have managed to fit the later guides. (upside down I think?)

I have never tried to install the MORSE guides with the roller chains.