I pulled the plugs on my 455, seven plugs are dark brown and the #1 is pretty white. Is that simply an intake leak or does it indicate something else. Cheers!
That may be why the B4B needs to be stagger jetted. Up to 3 sizes bigger jet in left front of the carb. If divider is cut and/or open spacer is used, the jet size may be reduced. I run one size bigger due to white number 1 plug. I also cut my divider down about 1/2 inch to help improve fuel/air distribution. No proof if it works, just want to avoid detonation. Kenne-Belle and other old Buick racers swore by stagger jetting with Edelbrock intake manifolds.
If a cylinder injest a small amount of water it will steam clean everything in that cylinder betmyound anything you can imagine
