Classic/Antique Car Repair: timing, small block chevy, rotor position

Question
yes my name is adam and i have a a small block chevy and i set the timing right and plugs are in the right fireing order and everytime i turn it over it still wont start and it back fires out the carb and headers and shoots flames and smoke and i have re-did the timing many of times..and it still does it and i am getting spark. what could it be?

Answer
It sounds very much like you have the distributor in 180 degrees off. Remember that the timing mark will come to TDC every revolution of the crankshaft but the engine only firs each cylinder every other revolution of the crankshaft. So, it can look like you have the engine timed right but that the distributor is 180 off. Mark the rotor position and pull the distributor. Install it so that the rotor is 180 degrees, half way around the circle, from the original mark. I'll bet it fires right up.
Brad