My wife Is driving a 73 electra show car, yeah I know why maintain an electra but It is a nice big safe car, It has a 455 with edel intake and holly 750 and the original points ignition. It was running perfect when we lived at sea level but now we are at 3500 feet and after recalibrating the carb I am still getting some black smoke when I show some kid what cubic inches can do to his little honda. I have gone down 3 sizes on the primary jets and gone to a brown spring on the secondary wich is 1 step stronger than original. Secondarys are still rich though and I don't want them to come on too much higher. also the primary mixture screws are only about 1/2 turn open to get a proper idle with every thing set to spec. Is this time to drill holes in the primaries? I hate doing that. I have tried cracking open the secondary some but it didn't help so I put that screw back where it was. It does idle great so maybe I shouldn't even worry about the idle circuit.
Also I have been thinking about replacing the point distributer with an electronic. Any recommendations? Mallory makes a comp 9000 but I have no experience with them. It isn't a race car but is a premium gas, high horsepower,big boat of a car and I hate it when my wife calles and says she can't get it started because it is raining. Points are weird like that sometimes. Original HEI's are rare for it and would have to be from a car a couple years newer. Most of them went to the crusher long ago so that is almost impossible. I am a mechanic and have absolutely no faith in rebuilt ones from the local parts stores either. If anyone has any hints or ideas please let me know.