Ditto on using the manufactuers’ recommended coil and/or ohm rating.

When converting from points ignition to Pertronix, I prefer the Ignitor II and Ignitor III modules over the Ignitor I.  The Ignitor I series does require the resistor on 12 volt systems and the Ignitor I is also prone to failure if the key is left on for extended periods without the engine running.  The Pertronix units do tend to be tricky in getting that initial distributor timing dialed in correctly before that first start up simply due to the magnet ring not being obvious in the magnet locations within that ring.  For that, I will take a paper clip and place it on that ring at all eight locations and mark each magnet location.  The distributor can then be rotated to appropriately align the magnet ring with the module for that first start up assuming the engine is coming up on the #1 compression stroke and the damper is located at 25° BTDC.

If I have any complaint with the Pertronix units, it is with the engine not having that snappy start as soon as the key is switched to the start position versus what you will see with a breaker points, MSD, Mallory Unilite, or Accel electronic ignition.

Lorena, Texas (South of Waco)

Anything you buy, Pertronix, MSD, etc. will come with installation instructions that include required components for compatibility. 

If the coil has an internal resistance equal to or higher than that required by the electronic module replacing the points that is sufficient. Adding a resistor will rob you of spark. If you have an MSD 6x installed the coil has to be compliant with the MSD box since the coil no longer talks to the distributor.


1955 312 T-Bird Warwick, NY

The coil I'm using is a Pertronix 1.5 Ohm Flame Thrower with no ballast resistor.  Never had  a problem with it.

great amount of info, thanks to the help of all those who responded. cliff

Yes they were. I don't know why there is a problem with the Pertronix. These wwere on cars running long distance not just from home to the local cruise. I've had the epoxy coil on mounted horiontally for about 8000 miles with no problem so far.
My friend has two MSD coils bad right out of the box also, it was on that other brand car but that shouldn't make a difference.

Aren't the original coils oil-filled and mounted horizontally?

Whatever coil you decide on check the primary and secondary resistance right out of the box. My experience with MSD coils has been primary as advertised but the epoxy filled secondary off by + several thousand OHMS (I tested 3 on the counter all way high). I have an MSD 6A and found the MSD8202 oil filled .7 OHMS primary resistance to spec but the secondary off by +1000, that’s the one I installed. High secondary resistance defeats the MSD. An oil filled coil wired correctly should be fine if installed with the polls horizontal to each other, after all back in the day that’s all there was. 🚙

1955 312 T-Bird Warwick, NY

Don't rule out the ACCEL 2020 kit - they work in all 1957-74 Ford distributors, are much cheaper than Pertronix, and are more readily available at most parts stores. For daily drivers, this kit has been my go to when guys want to replace their points/condenser units.

Daniel Jessup

Lancaster, California

aka "The Hot Rod Reverend"
check out the 1955 Ford Fairlane build at www.hotrodreverend.com

If you buy the Pertronix combo that includes the coil that most people sell it has an oil filled coil that is best mounted vertically. People have had issues with those burning out when mounted horizontally. If you buy the unit and coil separately you can get an epoxy filled coil that can be mounted horizontally and can withstand more vibration..