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Wasted spark VS Coil per cylinder?

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Hey guys, I think this might be my first post here, I mostly just lurk and read.

(Edit: if this question isn't posted in the right section, feel free to move it as needed.)

I'm interested in knowing about the limitations of a wasted-spark system compared to coil per cylinder.

I've decided to upgrade my old mopar V8 ignition system from a distributor to a wasted spark system using the quadspark module from DIY and a pair of their IGN-4 coils.

It seems like this should be a pretty substantial upgrade, and be easily adequate for my power levels. (Less than 100hp/cylinder with a little boost from a supercharger)

But it also seems that *everyone* doing EFI conversions is going straight to CNP now. Even OEM have been going that way despite the added cost and complexity.

My main reason for choosing the wasted spark system over coil-per-cylinder is admittedly mostly due to my personal packaging and appearance preferences, rather than anything technical.

The wasted spark system is a much easier upgrade to do stealthily compared to 8 separate coils.

Am I likely to be making any significant compromise by opting for the wasted-spark setup over coil-per-cylinder?

For 90% of applications, there will not be a difference betwen wasted spark and individual coils. Some OEM installations that may look like they are running sequential ignition using individual coils are actually running as wasted spark with two coils being driven off of a single output.

What you will likely lose (if your choosen ECU supported it) is individual trimming of cylinders for ignition timing, and if you have knock control then both cylinders will be retarded if knock is detected on either.

Thanks, that makes sense to me.

Depends on your coil charging/dwell time.

If you exceed the optimum dwell time on a wasted spark coil pack and hence have to reduce it and the resulting spark energy then you MAY be losing power.

If you don't then no difference.

At the time I built my 4age the easily wasted spark coil packs had a dwell time of over 8 ms which is also around the time between sparks on a 10,000RPM 4 cylinder engine. I went COP/CNP just in case I was going hit this and have to back off the coil charging time (either automatically or the ECU doing it for me.).

In reality it probably wasn't needed but I had the ECU outputs and the cost wasn't great so did it anyway.

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