Slant six dual exhaust proposal

A large single is almost always better than duals for a small displacement N/A engine. Resistance due to the gasses dragging against the inner walls of the pipe is a very big deal. It would take a pair of 2.5 inch duals to equal the flow of a single 2...and even though the flow would be equal, there would be zero scavenging effect because of the lack of velocity.
A Slant through a large single sounds better too. Throatier.