It's possible the Mallory system is a capacitive discharge setup instead of the standard HEI. That type works completely differently, actually firing the plug 4 or 5 times in the same time frame as the one hot spark from the HEI. It's easy to spot the CD secondary voltage pattern on an oscilloscope- - - -there's actually 4 or 5 spark lines in about 5 milliseconds. I prefer HEI systems to CD, but it's necessary to have a good battery to supply the starter and the current demand of the HEI at the same time. MSD systems are a good example of the CD setup. I'm not familiar with how the Mallory works, as I stopped using Mallory distributors back in the early 1980's.
Jerry
