pablohoney,
The 14-0901 kit comes with the 17-6822 coil that has a 37,000 volt output and a long spark duration. It also has a 4.5 Ohm primary resistance which when used with the 60 degree dwell angle PAMCO rotor results in a very cool running coil. Use 5K caps and non resistor plugs (NGK BP7ES) for good performance.
By comparison, the stock points coils only produce 10,000 Volts and thats at 12.5 Volts. At a lower voltage when starting, it's a wonder that the engine starts at all!
The 14-0911 kit comes with the 17-6810 "Green Monster" coil that has a 75,000 volt output. It has a 3.5 Ohm primary and also when used with the PAMCO 60 degree dwell rotor is a cool running coil. Use 5K caps and resistor plugs (NGK BPR7ES or Autolite #63's or the NGK iridium BPR7EIX).
The higher voltage from the "Green Monster" means quicker starts, especially with a low battery because with 75,000 volts @ 14.5 V on the battery, you will still get a very high voltage when the battery is low. Has been tested to produce a workable voltage even at 5 or 6 volts on the battery. The 17-6822 also works down to 6 volts, but just doesn't produce the same workable voltage.
The higher voltage from the "Green Monster" also means that you can open up the spark plug gap to .040 or more. A wider gap increases the exposure area for the mixture resulting in a larger "kernel" of initial flame for a more complete burn, more power and better gas mileage.
Just think of the mixture as it enters the combustion chamber. It's truly a mixture of some air molecules, some fuel molecules and maybe a few of each that have gotten together to form a combustible mixture, so a wider gap means that more of these molecules will be exposed to the spark to start the combustion process. The higher voltage from the "Green Monster" also means that the spark is hotter resulting in the ignition of more of the mixture that may not be ideal.
The 17-6822 coil accomplishes something similar with its longer spark duration. A longer spark duration also means that more of the mixture will be exposed to the spark over time. It just doesn't have the higher voltage and hotter spark of the "Green Monster".
The stock TCI needs 9 volts and other aftermarket systems need as much as 10 volts, which can result in hard starting when cold with a low battery. Some aftermarket system also require the engine to turn over at 200 RPM or they will not work at all. The PAMCO will work with 1 RPM at 5 volts. The engine also has to reverse 240 degrees to produce a kick back with the PAMCO, so it is very forgiving in a kick start situation. Points only have to back up as little as 1 degree to produce a kick back, as many of you would attest to!
Anyway, back to the coils.
Both coils will provide you with excellent all around service. The "Green Monster" does provide a better starting voltage and is recommended for use with the Iridium plugs in a more demanding situation. The "green monster" will also burn through carbon deposits and will generally produce a workable spark even in the worst conditions of plug fouling, over rich mixture or carbon tracked plugs. In other words, it will get you home with bad plugs.
The higher voltage from the "Green Monster" also means you can run a wider gap for improved power and mileage.
In any event, if you are looking to buy a system soon, Mike is out of stock for the 17-6810 coil which is part of the 14-0911 kit.