VTEC is the same thing as running economy cams in low rpms, and performance cams in high rpms. VTEC = POWER! i know because my buddy's '00 Trans Am just got worked by two Civic B16 Si(s) last night. i'm doing the built LS route though because it's cheaper.

and you can run boost on either motor. you'll actually make more power on a VTEC motor on low boost then an LS low compression on high boost. with a lower comp motor you have no low end, no torque, and once the turbo spools you bury the needle before you actually make any usable power.