I'm having starting problems with my 69 Mach. It has a 351W and a Holley carb. If I crank the engine (not start) and let off the key, it seems as if the engine "kicks back" and spits gas out the carb. Not good. I'm talking a bunch of gas, I had the hood open and gas was running down the underside of it. It seems like a timing problem, but 90% of the time the car will start fine and it runs perfectly. The carb has an electric choke. The car does this hot or cold. Any ideas?? Oh yeah, I had a Carter carb on it also and it did the same thing.