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Bosch Coil Resistance


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#1 hanra

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Posted 03 November 2025 - 06:10 PM

Just curious if anyone has a stock Bosch V8 coil if they could measure the secondary winding resistance. Mine is 7.74k ohms. I’ve another one here that is 9k ohms. Obviously the primary on both is 1.5 ohms.

#2 RoyalPlum76SS

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Posted 03 November 2025 - 07:34 PM

I have an old HEC716 which is listed for VL-VN era V8's, it measures 7.77K ohms.
I have a few more old torana/commy bosch coils but I'd have to research their long part numbers to know what they're off.

#3 Shiney005

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Posted 04 November 2025 - 10:38 AM

How do you measure it and can I do it with my old analogue multimeter?



#4 RoyalPlum76SS

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Posted 04 November 2025 - 11:02 AM

How do you measure it and can I do it with my old analogue multimeter?


So long as it has an ohm setting that reads in K ohms you can! Just put 1 lead on the h/t post and 1 on either of the +/- terminals and read away.

#5 claysummers

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Posted Yesterday, 07:51 AM

Tech from Performance Ignition (Scorcher) in Nunawadding told me resistance greater than 4,000 ohms indicates a healthy coil. This was in reference to a Bosch style HEI unit from a six, but I believe the eights use the same coil. Old school oil filled.



#6 yel327

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Posted Yesterday, 10:21 AM

I think I have a Bosch book somewhere with all these specs in them. Will see if I can find it.



#7 hanra

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Posted Yesterday, 02:47 PM

That would be cool! 



#8 hanra

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Posted Yesterday, 03:07 PM

.

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#9 yel327

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Posted Yesterday, 05:44 PM

I just checked, it only has Primary Resistance listed. That coil is 1.28-1.38 Ohms.






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