The Unilite is a leftover from the age of points where 6 to 9 volts instead of 12-14 was fed to the coil to reduce erosion of the point contact surfaces. A ballast between 1.8 ohms is pretty common for American production engines. MSD in the constant pursuit of hotter sparks sells a .8 ohm. Either will work but experience with the Unilite light says it lasts longer with a 1.8 ohm resistor.

Bogie

 

I read the Accel instructions one more time, and it dose say 1.35 ohm if not using a system with the inline resistor. That must be what i need, or am i wrong?

 

That will work the general range is .8 to as much as 5 ohms (Chrysler). It’s say 1.35 is close enough to what most American brand production uses. Once installed read the voltage on the output side. Should be between 6 to 9 volts. The Unilite can be run on full B+ which is roughly 12.5 battery to 14.5 alternator, it woks fine but shortens it’s life a bit. The original Unilite was intended for a drop in replacement for points. When automotive B+ changed from 6 to 12 volts in a period from 1953 to1955 depending on brand and model it was found that point contact material transfer greatly increased causing a crater on one contact and a mound on the other so resistors were employed either a stand alone or as a special wire to go back to 6 to 9 volts to get acceptable life span on the points.

Transistor ignitions using individual power transistors on a big heat sink began showing up in the early 1960’s. Big, bulky and hot running they didn’t last long. Technology developments through the 1960’s shrank these things to where they could be modularized and put under a distributor cap instead of a housing about the size of a modern 6AL box on the firewall. The Unilite came out in the early 1970’s as a replacement for existing point distributors and was designed around their use of a voltage limiting resistor so to the average guy they were simply “plug and play”. The OEM’s were switching to all electronic at this same time a common representative being GM’s HEI but everybody had something on that theme. So tye ever cost conscious OEM’s designed around using the available B+ generally referred to as 12 volts to eliminate the cost or resistive wires or stand alone resistors and their installations. After all “a penny saved is a penny earned”.

So anyway the original Mallory Unilite was a modernized for the period electronic ignition sold as a direct replacement for your points ignition. They even sold a kit that went into your existing points distributor to replace the points with a module.

Bogie

 

Thanks.

Just order a 1.35 ohm ballast restrictor and Mallory Voltage Regulator 29371. Will run full B+ to the Unilite through the voltage regulator, i may drive 1000km / year.

 

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