I used the rebuilt Holley 600 carb and am thinking that it flooded out the motor as was the case with the fouling plugs.....I had two carbs from my dad which were probably about 15-20 yrs old....we were going to use the rebuilt 600 for the car but decided that the edelbrock 600 was a better choice for regular driving....the other carb which I believe was a 650 Holley worked fine before we took out the motor in the first place (that got traded in for the edelbrock and some change)...timing is 8 degrees on the motor/////I am taking a break for a few days from the motor so I don't blow a f'in gasket