Choosing an ignition system
Ignition systems can’t make more power as such, but they can reduce power wasted. Meaning a spark that ignites the air/fuel mixture can do just that, or not. It’s a binary yes/no thing, either it ignites or it doesn’t. Some people talk about a warmer spark or longer, still the result is all about: Does the mixture ignite? Normal engines fail to ignite a few percent of the time. So a few percent of power and economy are wasted, that’s what a good ignition system seeks to avoid.
What makes an ignition miss? Inadequate ignition coil, old/cracking ignition wires, old/damp/cracked distributor cap. The best way to avoid this is to buy a complete ignition system from one brand name. Components from different brand names will usually work together, in fact in some instances what’s inside is produced on the same factory, but we’ll never know. Buying from the same brand name ensures it fits physically and the wiring is snap in. Of course it’s not a lot of work to connect wires outside the original terminals, but one wire wrongly connected could fry an ignition module. Besides, buying same brand is colour coded, looks better.
Ignition box
This is the most valuable addition assuming what you have already works. It produces a more lengthy spark or multiple sparks (MSD) or even manages to do 1 spark, test the cylinder if it’s fired, and if not, produce further sparks until it fires (Jacob’s). Electronics are fast! This helps a lot in ensuring fewer misses. It can’t really be felt when driving, but one thing that often happens when installing an ignition box for the first time is that the car starts more easily, it feels like it starts even before you finished turning the key. A good sign of what’s going on in the cylinder.
Distributor
Preferably with a module, not points. Points are OK when adjusted properly, but can go out of adjustment, the module never does. If the module fails (rare) the car stops promptly. The distributor cap is important. The bigger the better if you have room (an engine with blower often hasn’t). A HEI type/size ignition cap leaves more room between the 8 posts, significantly reducing the risk of firing the wrong cylinder which can destroy an engine. And be sure the holes/posts on the distributor cap matches the wires.
Ignition wires
Try looking under your hood at night with no lights on and the engine idling. Don’t stick your hands in there, but you’ll probably see plenty of sparks and arches around the wires if they’re old. New wires can contain the energy better and send it to the plugs where it’s supposed to go. Buy the best fattest wires you can afford. And buy spiral core. Solid core wires can induce a spark in the adjoining ignition wire, thereby creating a spark at a very inconvenient time in the wrong cylinder, a serious problem on cylinder 5 and 7 on a Chevy. This is avoided with spiral core wires.