I'm waiting for someone to fabricate a current version of this exhaust system created by Steve Weiner (Rennsport). The cross-over tube joins both sides and changes the resonance of the exhaust pulses - a common strategy performed on front-mounted V8 engines.
A variation of this would be some way of varying the ID of the tube using different "donut" discs sandwiched between exhaust flanges in the crossover or using the following elec. exhaust cutout to effectively vary the crossover pipe ID. In addition to modifying the resonance level, there may be some tuning opportunities for power.
Sherwood