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Old June 9th 14, 09:21 AM posted to rec.autos.makers.vw.aircooled
John[_28_]
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Posts: 359
Default Rotor, without the 12 k-ohms resistance

Would have been interesting to see the CRO traces. With an
inductive/resistive circuit the time constant is L/R so decreasing R makes
time constant greater which ties up with your results.
I wonder how a 0 ohm rotor with 10K spark leads compare?. For years I
constantly adjusted the chokes on my T3 carbies. After many years I
eventually realised the best way to adjust them
seemed to be how the VW service manual recommended!. I also agree with your
last statement!!!
John



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...



If you normally required a 5 kohm resistor and switch to a lower resistance
rotor you may notice a slight difference in engine firing. Compare the spark
produced by the 5 kohm resistor in the first trace to the traces for a 1
kohm resistor and one that has had the resistor removed (0 kohm). The 5 kohm
trace has a very sharp fall from the peak voltage required to fire the spark
plug, to the burn voltage level where the bulk of the current flows. This
results in the longest burning spark. As the resistance of the rotor
decreases, the length of time it takes to fall from peak voltage increases
and the shorter the spark. Don't try to outsmart VW/Bosch: they knew what
they are doing when they specified which rotor to use.

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