Hey guys I have a 57 Bird 312 / Fordomatic. Holley 4160. I just did the heads on it. Compression is 149 -155 on all cylinders. Leak down test also good. Vacuum is is almost 19. Timing set at about 10˚. Valve adjustments have been checked several times and they are all good. Floats also checked and below sight hole. Car does run great however i pulled the plugs and noticed that the front 4 plugs are noticeably darker. I pulled the plugs because I noticed my oil seems thinner and has some smell of fuel. Also exhaust fumes are strong. I have attached 2 photos. The 2 front plugs are really sooty. I did notice that when I removed the carb to do the heads the carb gasket was wet at the front of the carb at the front barrels. Is this carb leaking internally and fuel being washed down into the cylinders?