High energy ignition problems

October 1, 2019 | By Staff


I have a ’64 Le Mans with a newer GM HEI (high energy ignition). It ran great for 14 years on the original module. Now I go through them every two years and always on a hot summer day! I converted to an oil-filled coil to help keep it cool and used an MSD-made cap to run a sparkplug wire to cool from the center cap. The Idea was to keep heat away from the module. But I am hearing many on forums that are having the same issues with poor-quality modules. Do you have any thoughts and suggestions for a supplier of these four-pin modules with a decent warranty? DUI in Memphis, Tennessee, offers a USA-built module with only a oneyear warranty for $60 (Davis Unified Ignition; performancedistributors.com).

Any ideas are much appreciated.


I know I will get letters about what I have to say but here goes. I installed an after-market HEI system on a 1970 VW Beetle, and it only lasted a few miles before it got overcooked. I also have an HEI distributor on my 1958 Chevrolet Apache pickup on which I have replaced the module twice in five years. And then I tried an HEI conversion on my 1955 Chevrolet Bel Air station wagon and it failed in short order because HEI will not work with its Borg Warner overdrive. That’s because the overdrive shorts out the ignition momentarily to shift the transmission.

Your Le Mans is not a high revver, so if the original ignition system is in good working order, you should have no problem with coil saturation, and in all my years of tuning up cars, I have only seen a breaker point ignition system quit suddenly on one occasion when a condenser gave out.

To make the points last a long time, you can add an MSD transistorized ignition system that will make the points into just an on and off switch that will last almost forever. I am not a big fan of HEI for older cars. However, if you prefer it, you may want to put in another one of the type that lasted 14 years.