My 454 is not firing on the right bank of cylinders 2,4,6,8. The boat runs just on the left bank 4 cylinders. (all individual manifold pipes on this side where very hot). The right side header was cold? I checked firing order and wires and they are correct. I checked a for spark on a couple of the non firing cylinder and its present. The question is it firing at the right time. I appreciate your help!!