Why would a flywheel inrease hp's? The power comes from the combustion of fuel and air, plus some spark, in the combustion chambers. Seriously think for a second about how a flywheel does NOT fit into the scheme of things.

I know the Lima 2.3 and the Vulcan 3.slow use the same clutch setup, which leads me to believe that the Duratec setup isn't anywhere near a bolt-on. Either way, it won't increase the power output by 2.5x.

I doubt you can get much over 150-175 streetable hp's on a 2.3L, unless you want a Honda-like racer, period. Aside from a turbo setup, of course, but even that's pushing it.