Before performing any ignition system upgrade ya gotta make the motor run on whatcha got now. The upgrades won't "fix" anything that's broke!
The oem ignition system is far more than adequate to provide a stable signal for these engines if the distributor is not worn out, if the dwell is correct, if the base timing is ballpark, if the ignition coil is the correct primary value, if the battery is up top snuff during cranking output, if the switched primary feed voltages ("start" and "run") are correct, etc.
So let's make it run now and then upgrade after ya know the motor is gonna be a user!
Any "e-core" coil is far more efficient in actual operation than any canister-style coil. And far more durable also. Any canister coil is internally insulated with either pitch (tar) or oil and is subject to leakage when installed in a "lay down" manner as found oem on both IH stuff as well as chrysler apps. I personally have no use for the "epoxy" insulated conventional canister coils since they are nowhere near as efficient as an epoxy (or other type polymer potting) e-core coil.
The coil primary resistance ranges used with any add-on capacitive discharge conversions are designed to take advantage of the "step-up/transformer" design element provided only through the capacitive discharge boxes, canister coil primary resistance factors are limited, to nonexistent, so therefore one of the major advantages to the cd system is negated!
We can't run a coil with a primary resistance down in the 0.2ohms range on a street cd system , but those work beautifully on drag race stuff where the engines run no more than maybe 30 seconds total at a time. Super-low primary resistance coils will go up in flames when run more than a few minutes at a time without cooldown. The perfect coil match for any of the cd boxes is a coil with a primary resistance factor of between 0.4 and 0.7 ohms. A coil in that range must be used with either an add-on cd box, or is used with a "modern" computer-controlled ignition system with a crank/cam trigger setup,...those coils cannot be used with a pertronix, a crane conversion, a mallory unilite, a straight mag trigger conversion, etc. The "tfi" and "duraspark" version of e-core coils are wound with a different primary resistance factor compared to the versions used with any of the cd boxes,...yes, they are a vast improvement over canister coils, but are not suitable to use with cd boxes but work well with mag trigger conversions in stand-alone mode primarily for GM-based efi setups.
The "per foot" resistance factor regarding the spiral wound (for rfi suppression) secondary cables is my own subjective "opinion". Some of the cable manufacturers don't publish that data, but it's not real critical! But, we can't use "zero resistance" cables (as in stainless or copper inner conductor) on the street driven cd systems with the high energy coils either, the cd boxes do not like that stuff! But they are used with the full digital system in drag and circle track stuff with the correct cd ignition system (with all the bells and whistles). They also aren't considered "legal" for street use due to the rfi/radiation issue.
I'm using more and more of the msd "street fire" value line universal cable sets now in my work. The pre-terminated end connections are just as durable as the accel stuff and I like the black color for use where someone does not want the flash of the red, blue, or yellow jacket color of the other bands. I so no advantage whatsoever of using the 8.5mm stuff unless ya simply have it. The cables are far superior to any cable used oem all the way through the mid-90's and if a "spark plug boot puller" (along with boot grease which is imperative) is used to remove the silicone boots from the spark plugs when needed, they are a lifetime investment.
The msd cables are about $5 a set less for the same item from accel in my local market. The next step up in the msd cable offerings again is a total waste in my book. There is a tremendous amount of hype that surrounds all the "spark plug cable" business!
