OK, first things first- - - - - -is it making a spark? Pull a plug wire and use a spare spark plug to see if it can develop enough voltage to fire the plug. Just make sure you don't hold onto the plug while you're checking! The HEI system is supposed to develop at least 50,000 volts on open circuit, so it should make a healthy spark. If it's weak, or there's none at all, you'll need to check on the 12 volt supply to the distributor cap. This wire needs to be a #10 size, directly from the ignition switch, with no ballast resistor. The thin, silver-colored wire that used to supply the + terminal of the coil for the point-type distributor is a resistance wire, and must be bypassed to run an HEI system. If there was a ceramic resistor in the primary circuit, trash that one, too!
If the HEI is a new unit, it will probably work OK with the right voltage input. If there's still no spark, swap it for another distributor. Be sure the cylinder that's on compression is the one that's getting the spark by pulling a plug, cranking the engine with your thumb over the hole, and making sure the distributor rotor is pointed at the right cylinder when you feel compression. Set the timing just like you would with a point-type dizzy.
Jerry
