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Coil on Plug (COP) compared to Coil Pack and Ignition Leads

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Coil on Plug (COP) compared to wasted spark with ignition amplifier (ignitor), coil pack and ignition leads. Tried a search on the forum. Nothing came up.

What are the advantages and disadvantages of both please? The car is a competition car used in hillclimbs and sprints. Not used on the road. I use a Syvecs S6plus ECU.

From a reliability point of view, smart (TTL drive) COP seems to be simpler and I just need to carry one spare COP coil with me, rather than a coil pack, ignition amplifier and ignition leads. The Syvecs can do sequential ignition, if that is an advantage?

Would welcome your views please. Thanks.

I think that would be about it, but there is a third option, if you can't find a COP that suits/fits, and that's using a set of external coils with leads - you may find a greater range of options and you can mount them in a cooler area.

Thanks for replying. I can use Honda K20 coils and a couple of people do fitting kits for my (non-Honda) engine, so COP not a problem. However, the heat factor you mention is worth considering, as it is a turbocharged engine. Thanks again.

For most car engines running to less than about 9000RPM there is no significant disadvantage of wasted spark compared to direct. Above about 9000RPM your cycle time may start to limit dwell which may mean less available ignition energy. At similarly high RPM the coil duty cycle can become high and over-heat the coil too.

The only other consideration worth mentioning is if you need to run a lot of retard (say antilag) then with wasted spark you can be limited how far you can go as you reach the point where your spark will ignite the intake charge on the wasted cylinder.

Thanks for the reply. Some useful information there. I'm never over 7500rpm, but antilag is a possibility following my winter mods programme planned for 2020/2021. Thanks again.