I've run into a problem that has me scratching my head. I've rebuilt my car from the front to the rear and it has run fine for around 1,000 miles over two years. I have electronic ignition, Holley 1841 carb, 312 with auto. The other day I got about 10 miles from home driving on surface streets and all of a sudden the car started running rough. I got turned around and headed home with the car only able to run around 30 mph. At no time did it backfire just wouldn't run but if I gave it a accel pump shot the motor would pick up and then die back down. So I'm thinking that I have a fuel pump problem. I got a electric pump from CASCO so I mounted it in the body brace bracket by the front door. It would pump fuel through the stock pump (which was new at the rebuild). It this point I'm thinking I'm good. A few days later with the outside temp a few degrees warmer I started out and this time when about 15 miles on surface streets the engine started to act up the same. I switched on the electric pump and no change. The motor would still pickup with a accel pump shot but then drop back to around 30 mph. Again made it home ok. I checked the fuel filter and it was free flowing, I pulled the bowl off the Holley along with the jet plate and blew out all the passages but there seem to be nothing wrong. Checked the needle and seat, I couldn't see anything wrong. The bowl was as clean as it could be. The float level was fine. Again the new electric pump filled the bowl so it's working. The car again ran fine but I haven taken it very far. If the problem is vapor lock I wonder why the electric pump didn't help. Does anyone have any suggestions? One more thing when the car was running poorly I could rev the engine very high without any issues so I'm pretty sure the problem isn't ignition related especially when a pump shot will pick the engine up.