Don Terrill’s Speed-Talk

NewbVetteGuy wrote: ↑Fri Jul 23, 2021 1:52 pm ...
I'm definitely keeping the resistor plug spark plugs (for increased spark duration as I DO care about fuel economy)...

Spark duration actually decreased with resistor plugs.
Example of three different resistance values

Chrysler Crossfire coil is probably same as used at some Mercedes Benz engines. Bosch 0 221 503 035 It is a real dual coil (two separate similar coils). https://lh3.googleusercontent.com/pw/ACtC-3ckGZWBPCyUDRbNBxgHVjVjGCDBwMF9uo4mEaRwl4wvlRYQYYI3BT9FeIXnnXoP0jYmpfOkBF_RLWq_nkfKWk2-8NtqAjX6ZM7rGpWA3l...

There are a lot of motorcycle coils built similar to that. Can You tell some example (I can try to find it and test)? I'm almost sure, that there are'n any motorcycle coil like this (one primary winding / two secondary windings). Early model with wire to other cylinder are probably at waste spark, ...

Just wondering about the coils for Gen 3 Hemis. Seeing they connect to two spark plugs, are they internally two individual coils or one double-ended coil like on a wasted spark setup? One coil, two ends ... positive and negative. No. One primary and two secondary (weird idea #-o ). These curves are...

Stretch specs from website.
https://arpcatalog.com/26/

Thanks for thanks ....

One more, now example, that High Voltage probe can show a fast Risetime too.

Mercury 339-832757A coil 230us Dwell (~100A peak current)
Yellow = Primary voltage
Cyan = Secondary voltage
Blue = Secondary current

And more, now with CDI.....
Not much difference.

Yellow = Primary voltage
Cyan = Secondary voltage
Pink = Primary current
Blue = secondary current

MSD6A + Crane PS92 AEM TwinFire (Twin Trouble) + Crane PS92 AEM TwinFire (Twin Trouble) + MSD8230

Some example of RiseTime. Primary (100x probe) / Secondary (Tektronix P6015 probe = 3pF) voltages. About 5mm free air spark gap. First, IGN-1 coil, 6ms Dwell. NewFile2.png Like first + 22pF capacitor connected from secondary to GND. NewFile3.png Like first + 100nF capacitor connected primary - to GN...