Chevrolet Repair: odd misfire, head job, firing order

Question
just completed head job on 305 cid chevy,new heads,gaskets,plugs,wires,cap,rotor,carb(4bbl) all 8 cyls are firing but #2,3,5,&8 seem to be firing out of sinc while #1,4,6 &7 are working fine.just happens to be every other one in the firing order.can you help point me to anything that might cause this ? have never run across this before

Answer
Hello Dale, I would first check the intake manifold to see if the cylinders your having the problem with are on the same plane in the manifold. There is a upper and lower plane in the manifold. Follow the runners to see if they are. If they are then your problem might be the carb not suppling gas to those cylinders. The carb has two sides, one for each plane in the manifold. This would not be ture for a hi perf manifold that is only signal plane.

I hope this helps and let me know what you find

Have a Great Day        Mark