WRT carb bores closer to ports for the end cyls:
Many of the 2 X 1 carburetor manifolds (Offenhauser. Cyclone, Edelbrock, Edmunds, Ellis, Sharp, & Weiand) position the carburetor bores exactly mid-way between the end (1-2, 5-6) and center (3-4) intake ports, which IMHO still favors the center cylinders since they are drawing from both carburetors.
This Fenton 2 X 1 moves both carburetor bores closer to the end ports to address this. How much of an improvement? I have no results to report.
I also suspect that the cylinder-to-cylinder mixture distribution may not be constant throughout the range of RPM and engine vacuum. Many transparent manifolds tested with smoke have produced surprising results.
