I have a 1986 Chevrolet K10 Silverado 4x4 with a 305 engine that has been totally restored..the engine is still original as to the best of my knowledge...Last week the truck started skipping terribly and backfiring really bad...I took it to the local dealer who said they thought it blew the power valve in the carb...(holley 650)..so they rebuilt the carb...changed the plugs..checked the timing....checked the module in the distibuter...and It did'nt fix it at all....they said I need a new carb...I bought one today..installed it and it is exactly the same....it will start...but runs really rough and will go dead when you go down the road when you get up to about 15 mph....this problem started out of the blue and I am scratching my head trying to figure it out....do you have any suggestions.....thanks...Marty

Optional Information:
Year: 1986
Make: Chevrolet
Make (other): K10
Model: Silverado
Engine: 305...5.0

Already Tried:
Rebuilt carb...checked timing...checked module in dist...plugs...wires....new carb...