it's only a lowly Kent Formula Ford engine but I have noticed there is quite a step-out in the opening of the exhaust on the pipe manifold.
The pipes are a much larger bore than the outlets on the head.
Q. Would this step create enough turbulence to result in power loss by creating back pressure and upsetting exhaust flow?
Q If so how much? Anything significant?
I wonder if there is an advantage in funnelling out at that point or am I whistling in the wind and just need to put my foot down further and close my eyes more...