92 firebird starts and then dies

hi all... have a 92 firebird with a carbed 305. the car was sitting for 6 months. replaced the battery and it started right up. it ran at a smooth idle for about 15 minutes. waited for it to get to operating temperature. then it stalled. tried to restart it. it starts but then dies. if i start it and pump the gas pedal it will continue to run but very rough with the rpm going up when i pump the pedal and tries to stall. it also back fires thru the carb. was thinking water in the gas tank. the car had between 3/4 and full tank of gas. i replaced the fuel filter but no help... been a long time since i was a shade tree mechanic.. any and all help is appreciated.

thanks
greg:confused:

How many miles on the car? Can we rule out any mice chewing on your wires...they seem to love that stuff. It sounds as if the distributor might have gotten loose.. Thats the first thing I would check..Check ur fuel pressure....Is that carb the original? Another possibility is that the catalytic converter is clogged