I run good old 93 octane pump gas, I had to back the timing up like a degree, back to 15 (stock is 16). As far as WHP, I don't have the fogiest idea, but as you asked, If I were to guess, after I go spend some time on the dyno doing a little tuning, I'd say in the neighbor hood of like low 220's maybe if I'm lucky high 220's.
As far as the flywheel, I wanted an aluminum flywheel, which both the Spoon, and Toda are chromoly, and also a hell of a lot heavier.
Name isn't always everything, and often it depends on what your looking for a part to do. I didn't want to knife edge my crank, but wanted to lose so weight off the rotating assembly, and that seemed like a good way to do it.
On a side note, we've had problems with chromoly steel flywheels chipping teeth on our starters, not to mention the Jun ones we were running for a while which are chromoly tended to warp rather quickly, I think it's more due to the fact that they shave a little too much off, but not sure if it's because it's chromoly alone.
And about the warranty thing, my warranty is still good till Nov. of 2005, or another 22000 miles, all the motor work I have done is internal, and unless the start taking the stuff apart, I don't think I'll have any problems with my warranty work, so far, I've just tossed a hat over my Vafc, and just made sure I switched ECU's back to the factory OBD2 before I go in. There's not a lot that would go bad, other then maybe some sensors, and I think that they wouldn't look into it enough to find out that I moded my car. I don't have a cut valve cover, and the only things that are noticable that I have different are the headers, and intake, which are both comptech, which they warranty anyway. on top of that, if all else fails, I just throw the tech some money, and they ussualy don't say anything.
Later!