I'm in the same boat as you except I've already spent a lot of cash on Skunk2 Stage 1 cams, cam gears, VAFC, and dyno time. After all that money and time to install, I'm at 154 whp, barely over what a stock GSR puts out. The orque on our Si's suck, too. I'm starting to think that I should take all the aftermerket stuff out, sell the Si, and start over with either a GSR or Type R (1st choice of course). Most of my engine parts are interchangeable, so no real money lost...

Hind sight is 20/20 as I should have bought a GSR to begin with but was hesitant due to $400 more per year for insurance on the GSR over the Si.

Oh well.... Enough of my rant.....