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If this is a pure-power always-go setup with max-torque fueling everywhere, and no typical racing or street fuel reduction tuning, CDI/multi-spark can work well. If going for cruise or race fuel-reduction tuning, stick with high-energy systems for their benefits. Lots of options there if that's part of the project goals. (y)
 

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I don't suggest the blue grommet DuraSpark, as it is only a little better energy than points. It will certainly run the engine, but will encounter misfire sooner at either high-load (accel or peak-torque) or leaning for race or street economy before HE power will. Same for CDI/MSD with their short and sharp sparks, which need more sparks to get better burn, but only available at lower speeds. I would suggest the red grommet DuraSpark with HEI power if wanting that setup, or many other HE options. My favorite is programmable controlled timing for max flexibility with easy tuning, using a DuraSpark distributor and HE coil, or multi-coil setups.

Oscilloscope trace examples of low and high-amp spark burn durations, the short one representative of points or CDI (low-amp but much higher voltage), and the high-amp HE long-burn. You can see the HE burn provides a longer time for igniting more mixture for wide-rpm and lean-burn mixture ignition. Another option with the greater power of HE ignition is wide gaps, which shorten the burn somewhat, but expose much more mixture to the spark for quicker and more complete fuel burn:
Rectangle Purple Slope Plot Font
 

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Not saying you should do anything specific without more info. The vast majority of users here will do well or best with HE ignition, but that's most, and not you. Suggesting to always roll back to project goals. What the engine is and how you will use it will point in specific directions. Every type of system has specific pros and cons, which is why there are so many of them. Do most of them run the engine and "work" for most things? Sure. And so we have all kinds of opinions and arguments about it, because "mine works fine". Define "fine" and how you compared to optimum for your project? ;)

Not my first pick, but if wanting a DS system for whatever reason, you can build your own wiring, cannibalize it, or buy a new harness (check with Painless or American Auto Wire for DS-1). To get the red-grommet box, just shop for a '77-'79 California car (not 49-State) like the Standard LX210 box. Stick most any HEI/TFI-type coil on it (B-2 is fine) and run. That's an example of one option, depending on your preferences. Some will jump in and push for a simple P-II conversion, or FAST or XR-i equivalent, or other system that performs similarly. Try to stick to systems that fit your project best, pick one that makes you giggle, and enjoy your ride. :cool:
 
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