Hi guys, we got this car from my dad, not the prettiest but it goes. It needed a fuel pump but ran with the leaky one, changed it out, and now that it has gotten just a little bit warm, you can run it down the highway ok as long as you dont have to stop for any thing before you get to your final destination. If you stop and turn the engine off(after engine is well warmed up), get gas or pick someone up(short stops), it will start ok, go for about a 3 blocks and dies, and acts like it is not getting gas, but the pump is pumping. The only way it wants to run is if you cut all air off from the carb (we hold our hands over the carb to cut the air). Its wierd, I know. Then if it cools down partically all the way, it runs and your off and going. What could be the problem, heat expansion of some kind, vapor lock somewhere, vaccuum, etc, any suggestions would be appreciated.

Thank you