Thread: Do P12 20v coil plugs have built in ignition modules?

I'd be curious how it would read if you hooked up the inductive pick-up after the coil's high voltage output.

Maybe it's an AEM thing? The dwell time is the major factor here I believe.

I also found that I couldn't get an accurate timing reference from the wires feeding the coils in a COP setup. With the timing light I've got, it reads about 15deg too advanced at idle and increases through the rev range in the way you described, although I only tested it with the timing light hooked up to the signal wire.

It's important to note that the way the coils are signalled is that the signal wire goes high (12V) to start the dwell period, and then drop low (0V) to end the dwell time and fire the spark. I suspect that my timing light was picking up on the rising edge at the start of the dwell period, and that the timing lights used by Nissan were probably designed to pick up on the falling edge - in which case the loop would work.

Just as an update, Josh and I were talking and he mentioned Ben's plug wire trick on the end of a COP to test timing. I found multiple references from Nissan techs about this and they all said they do the same thing. They basically have a special plug wire that goes on the spark plug and the opposite end plugs into the bottom of the COP and they use an inductive timing light (standard timing light) to verify timing with the factory timing marks.

Ben and Josh use an 8ga. piece of wire to connect a stock SR plug wire to the end of the COP and use the inductive light on that, which is basically the same thing. If you can find a plug wire with a straight end on the dist. cap end, then you can crimp the metal prongs closed a little and have the same thing.

Brent

they make a test light for coils that u can use to do this trick. it shows you when the coil fires and its a regular plug wire so u can attach a timing light to it.

i run the cop setup on ve race buggy, and it works great once tuned. no problems, no messy leads. i aslo changed the 20v rocker cover.