Dont give up that easily !!!, if you want more speed out of your car, this is the most cost effective and simplist way. The rolling road would make the job quicker, but if you raised the booster presure slowly, changing the pulley rates, using bleed valves you could gradually find the level at which the engine starts to ping, then back off the boost. Using a cetrafugal blower which is essentialy a gear drive turbo, with out all the hassle the turbo gives, you could add 40% power, change the compression ratio and you could double the power !!!