usedknobby

no spark I know this has been covered a lot and I have tried most of the suggestions but to no avail. 70 road runner 440 stroked to 512 almost all parts from 440 source. No spark this is what I've done so far, took bulkhead apart cleaned all connections that looked good replaced all that were bad, tested all wires for continuity, New ecu, New ignition switch, New coil, new distributor from 440 source new plugs and wires, here is what is happening no spark to coil on crank circuit ,run circuit is good because strangely enough every once in a while it will start and run good but next time it won't start for several try's. Here lately it wont start at all. The only spark I have with a plug in number one wire out where you can see it is immediately after releasing the key from cranking it will give a spark I assume this when the run circuit trys to work. Also replaced the ballast resistor forgot to mention that earlier. Hope I have offered up enough info for someone to figure out what's going on with it Thanks will look forward to what everyone thinks