there is probably more to it than just diameter of exhaust. How much is to be gained by eliminating one of the cats? or tossing the mufler in favor of a cherrybomb or better high-flow mufler? removing the resonator? exiting before the rear wheel as apposed to all those bends to get it way back there?
I talked with Bob Garner at TRD Monday...still no news on the Gen 2, but he says they are still trying. He said there is more than enough demand, especially with SA and Middle East markets. But he says the decision is mostly political now.