TR2/3/3A Pertronix coil on TR3?

[White79MGB]

I am almost convinced that I want to install a Pertronix electronic ignition on my TR3. What about the Flame Thrower coil? Is this required or desirable to have in addtion to the Ignitor? The Pertronix lit states that the flame thrower is for non ballasted systems, and I am just a dumb mechanical engineer and don't know what a ballasted/non-ballasted system is...!

 

[martx-5]

A ballasted system just means that there is a resistor or resistor wire going to the coil that drops the voltage down. I'm not sure to where, but probably around 8 volts. In such a system, there is also another wire that comes from the starter solenoid to supply a full 12 volts when starting to get a hotter spark. The TR3 does not have any ballasting going to the coil. I don't know whether there is an internal ballast in the coil or not. Some coils have them. That shouldn't matter it you are putting in a matched system. You might have to convert to negative ground however, unless Pertronix is available with positive ground.

 

[Keoke]

HI W79MGB, It is not mandatory that you use their flame thrower coil.I would suggest that you first install the Pertronix conversion kit using the provided instructions, and run the car. To check the coil out you have, measure the DC resistance between the two terminals. If it reads ~ 3 ohms it is operated in an unballasted system. At ~ 1.5 Ohms your system is ballasted. the instructions cover both systems for you.Both Positive and Negative ground kits are available and be sure you order the proper one. Try "Retro Rockets" for the best price---Fwiw---Keoke