Pertronix is a proprietary system with its own electronics and a dedicated design coil in some applications, so a failure leaves you stranded until you can diagnose the problem and order replacements from the manufacturer. Some of the members here have experienced repeated failures of the Pertronix system, while others think it's wonderful. General Motors HEI parts are available at any corner parts store, and they're usually virtually bulletproof. The HEI distributor housing needs a little adapting to fit a 216/235/261 engine properly, and sometimes a change to a different drive gear material to work on a stovebolt engine. Personally, I prefer the GM system.
Jerry
