We got some of the hurricane this morning and I had to do a quick maneuver to avoid tree debris this morning. As I came out of the S style maneuver the car started doing surging or pulsating like you get when you have bad gas, car still shifts smoothly through the gears, cranks easy and idles fine. The surging is at low speeds and light on gas but if you push the accelerator on down the car accelerates fine The car is a 69 with installed its original factory Autolite 4300 carburetor on 351W. I had the gas sending unit out in January and all seemed clean and I had sent off to be rebuilt in Arizona, have new filter at carburetor and the car was running like a sewing machine before the sudden maneuver. Any ideas??
Float level in carb bowl could be low causing fuel starvation when the gas in the bowl is sloshed around during fast turns. I have the original 4300 on mine too and it’s a finicky beast at best.
Do you think the carburetor needs a new float?
Bad floats usually sink which would cause flooding. But the little metal tab on it could be bent causing low fuel level in the bowl.
I wish there was a new carburetor I could purchase that I could easily replace the 4300 with.
I had mine rebuilt at All American Carburetors in FL. They did a great job and stand behind their work. Catlover suggested this carb as a replacement for my 600 cfm version: