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Re: Coil Pack Testing
Posted: Fri Jun 23, 2017 8:20 pm
by vlad01
Oem ones 2ndary are constructed like a capacitor, having a copper foil coil with a separating dielectric foil wound together. Basically the full potential of the 2ndary would need to break through n times the turns of the coil layers worth of the dielectric where as the other designs it a lot easier to break down the enamel and surface give most of the wire is packed together with not much else dielectric.
I would take genuine oem over else any day of the week. All my coils lasted 23 + years with no less that 400k except for one exception at 200k as I killed it through water ingress using a pressure washer directly on the coils.
Re: Coil Pack Testing
Posted: Mon Jun 26, 2017 8:18 pm
by OZ38
Is there a easy way I can test my coils to find the dodgy one ? I don't really want to put one coil at a time back on to the car to see if it falls over unless there is no other option available.
As in the end I just change the full set with another full set I have. So now I have two full sets with one (???) dodgy coil each lol.
Re: Coil Pack Testing
Posted: Tue Jun 27, 2017 6:12 am
by MAGP
I found mine by running the engine and pulling the leads off 1 coil at a time. Pulling a lead of a dead coil doesn't affect the engine speed so you should notice when there is no change.
Re: Coil Pack Testing
Posted: Tue Jun 27, 2017 9:56 am
by jenko
try ohm meter test across two output posts dodgy coil will be different resistance ,from memory they should be around 11k
Re: Coil Pack Testing
Posted: Tue Jun 27, 2017 11:08 am
by The1
some of the dodgy ones ive tested still read ok, as they still do work, only the voltage is down.
Re: Coil Pack Testing
Posted: Tue Jun 27, 2017 11:10 am
by The1
antus wrote:Its interesting that they show 9 vs 10 coils between the zzp and msd, implying with out saying more is better. Im not going to comment on if that is true, but because its the low voltage side of the coil having 9 instead of 10 is probably how MSD get the higher voltage spark, 10 is probably closer to OEM but its not clear from the images what the OEM ratio is. Also this is assuming the same number of coils on the high voltage side, which Im not going to attempt to count and without doing so makes the results inconclusive.
I like that the OEM coil has coil loops over more of the transformer core with even distribution. It actually looks to me like the best of the 3.
it doesn't look that different, apart from the fact OEM is in one chunk compaired to aftermarkets doing it in a spiral, perhaps it effects the field more?
Re: Coil Pack Testing
Posted: Tue Jun 27, 2017 11:46 am
by vlad01
The1 wrote:some of the dodgy ones ive tested still read ok, as they still do work, only the voltage is down.
Same. I found pulling the leads and drawing the spark until it breaks down and note the length. I found most dodgy coils that work ok but break down under load show sparks 1/3rd less in length generally.
Re: Coil Pack Testing
Posted: Wed Jun 28, 2017 7:06 pm
by OZ38
The1 wrote:some of the dodgy ones ive tested still read ok, as they still do work, only the voltage is down.
Could I interest you in testing my 8 coils of unknown condition ?
Seeing as you already have the tester set up, it would be a better test than what I could do currently.
Re: Coil Pack Testing
Posted: Wed Jun 28, 2017 7:41 pm
by The1
Pm sent
Re: Coil Pack Testing
Posted: Thu Aug 03, 2017 10:46 pm
by L67PSI
Has anyone tried / tested the Yellow Jacket coils??
Link -
http://yellowjackets.com.au/race/produc ... mh-38v6-2/