The engine turns over and it is getting gas.
OK, just to be sure we're all on the same page- - - - - - -The engine cranks (starter turns the crankshaft), but the engine fails to run, right? When this happens, have you checked to see if the spark plugs are getting voltage? The simplest way to do this is tro pull a plug wire, and stick a spare spark plug into the end, then hold the plug shell against a ground (insulated pliers, please!) while somebody else cranks the engine. You should get a nice fat spark across the plug electrodes. If not, check the "Bat" wire going to the HEI cap to see if it's getting battery voltage during cranking. (should be 10.5 volts or more) If not, check the ignition switch for an open circuit during cranking. HEI systems put a big current load on the ignition switch contacts, and pre-HEI switches aren't designed to carry the load for very long. If you're getting good voltage to the HEI, you've got a choice of a bad module or a bad trigger coil. The wires fron the trigger coil to the module move all the time if the vacuum advance is working, and the wire strands can break inside the insulation and become intermittent, dropping the signal to the module periodically. The ignition switch is the most common cause of an intermittent no start condition.
Jerry
