Senior Tech Team
Join Date: Apr 2012
Location: Yerington, Nevada
Re: Spark plug gap & Pertronix Ignitor
"Seat of the Pants" dyno is the ONLY tuning device I ever use.
With any inductive ignition sysem, it is coil saturation dwell for storage of the volts into the cpil that makes the spark level. The ONLY differences are, HEI electronically increases the dwell time, which is coil saturation, to make more volts, and MSD type Capacitor Discharge systems that charge not the coil, but the capacitor, which then tells the coil to "make 40K volts" spark.
One thing I always thought was very interesting about PerTronix coils (the oil filled round ones are fantastic good, the epoxy, pure junk) is that on the box, it states "40,000 Volts". Then the words, in (...), (AVAILABLE). That does not mean the coil will make 40K volts on any and all ignition systems, all it means is that IF there are electronic drivers, such as capacitor discharge, to charge the coil to that level, the coil is ready to make that voltage. On average, for a coil in cap HEI that runs 60 or so deg/F HOTTER than a remote coil ignition, the coil n cap HEI's only make about 14K to 16 K volts, when they get up to operating temperatures.
Coils run off the cap make about 28K to 32K on average, this is why both Mallory and MSD made/make coil adapters for the large coil in cap HEI, TO MOVE THE COIL OUT OF THE CAP, AND USE A NICE, COOL OIL FILLED COIL, LIKE THE OIL FILLED ROUND PerTronix COIL.
Using PerTronix think, adding .005 to a stock plug gap, which is usually an .032 setting, we would get .037. Close to Gene's settings.