Richard A. White wrote:Just to muddy the water...here is my P30...side view
I should have been more specific in my post. The runner portion is smooth on the P30 as pictured. The P35 and P40 have ribs all the way along the runner. All of the larger motors had some type of ribbed reinforcemnt in the flance area. I have seen quite a few A series manifolds that are distorted where the cylinder type wrap mounts. I would assume that this was caused by heat, but not sure.