It makes sense to me . . . have the carbs-on-the-left. Less intake runner and more direct shot of fuel and air to the valves. But then you have less time for the fuel to atomize, turn to an oxygen rich mixture of gases ready to explode. Huh. I'll have to ask Kevin Baas how his dual-carb panhead(carbs off the left) performed? I never heard him complain about it. The long intake manifold runner on a panhead, I always figured kinda worked like a tunnel ram on a V8. A larger amount of gas and air getting all mixed and sucked in for a huge explosion. The more gas and air, the more power.