when im driving the car will just quit the Gen light does not come because all electrical power is gone ..when I pull over there is no power,,the lights don't even come on..when I cross terminals on starter lots of power,but the rest of the car is dead dead 64 impala 327
Check the wire connectors at the firewall (engine side). This is a classic problem with these cars. The main power wire terminal in the connector is easily overloaded and cooks or gets corroded. Sometimes giving it a wiggle works, cleaning it works better, but the ultimate solution is replacing the wire harness on both sides. By the time it starts doing this, the springeness of the connector has been cooked out of it, and maintaining a good connection is difficult.
You can see the two connectors below and a bit to the right of the wiper motor. The plastic shell has a loop on the top and bottom that goes over a barb on the firewall side. A small screw driver lifts the loop over the barb and it should slide off. As I recall, (could be wrong) the culprit is the big yellow wire, it is the largest gauge wire in the bunch, in any case.
The stock wiring was carefully made to save money by using the least amount of copper they could, so the wires are only as big as they need to be. They did not dream of the aftermarket gadgets that would be hooked up in later decades, like stereos. If you do install extra goodies, like a stereo, it is a good idea to run a dedicated wire from the battery (with a fuse near the battery!) to the inside of the car to take care of the extra load.