Jag spark timing

[Walter Petermann]

This was kind of a mystery to me too. The wiring diagram for the fuel and
ignition (one ecm does both) shows only one sensor and (aparently) the
ignition is not 'wastefire'. I posted the question to a Jag group and
got the answer that for each notch (3 notches) the ignition rotor has a 
unique position (one of 6) so the spark will always go to the correct 
plug. 

 Walter

Ken Kelly wrote:
> 
> For the Jag to work it must have another sensor to indicate
> the Cam position, or use wastefire coils that fire both
> cylinders at top dead center on that crank position.
>                 Ken.
> 
> Walter Petermann wrote:
... the Jaguar XJ40 uses only 3 notches for the
> > timing or 120 degrees!
> >