vtec is good but primarily it was implimented to improve gas mileage, not necessarily performance, with a similarly ground camshaft on the same sized engine with the same compression rating u will get the approximately the same hp ratings, but u will loose gas mileage because vtec engagement doesnt kick in unless ur ecu notices ur want for the power or the rpms for it, vtec is simply the same as having 2 camshafts one for low rpm operation under normal driving conditions (gas saving mode) and 1 for all out power (gas guzzling mode) all in 1. both the zc and b16 are great platforms in a rex due to its low curb weight.