Ignitor I: Part No. 1181 This is the basic points replacement unit and has 2 times the energy of points and the resistance wire is not an issue whatsoever. They can be run with a stock points type coil or a Flamethrower 40,000 volt Coils available in 1.5 or 3.0 resistance values and available in chrome or stock looking black. This unit works fine with a stock engine. Ignitor units operate off of a magnetic wheel that mounts underneath the rotor. You will have to make sure to take any end play out of your distributor to maintain the proper gap.
Ignitor II: Part No. 91181 The next level has 4 times the energy of points between 3000 and 5000 RPM operating at it’s full potential working with 12 Volts and features Adaptive Dwell. My experience is that the Ignitor II will work fine without bypassing resistance wire for stock and mildly tweaked pump gas engines up to 400 HP, just not at full potential. I would recommend however you check the available voltage at the coil with the ignition on to check the health of your resistance wire before making a choice. If you have about 10 volts, you should be good to go. I had originally tested my Ignitor II at both 10 and 12 volts and didn't notice any difference. An Ignitor II low resistance coil is recommended. Ignitor II 45,000 Volt coils are .6 ohms resistance and available in chrome or stock looking black. The Ignitor II units also operate off of a magnetic wheel that mounts underneath the rotor. You will have to make sure to take any end play out of your distributor to maintain the proper gap.
Ignitor III: Part No. 71181 5 times the energy of points between 3000 and 5000 RPM operating at it’s full potential and has a built in Rev Limiter. It also features Adaptive Dwell and Multispark. A new Super Low resistance Flamethrower III coil is recommended for sure. The Flamethrower III 45,000 volt coils are low .32 ohm resistance, quick charge, and available in chrome or stock black. The Ignitor III units operate off the points cam. With it’s additional features including Multi-Spark, the Ignitor III must have a full 12 volts to the coil to operate properly, period. The unit also senses startup increasing voltage and adjusts the timing which can come in handy on an engine with a lot of initial timing in it. (The matching Flamethrower III Coil is under Summit Racing Part No. PNX-44011 for Black, and PNX-44010 for Chrome). An advantage of the III over the II, is that it does not require the removal of the distributor.
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The new "Lobe Sensing" versions of the Ignitor Units (i.e. 1181LS and 91181LS) do not require removing the distributor.