People know that any and all of the "power boost" that comes from a LS/VTEC setup is derivative from the facts that the B18B has a slightly higher displacement, and usually the machining of the head and other components that's associated with the install itself. A stock GS-R block has FAR more potential with more reliability than a LS/VTEC block.

Look at it logically: If honda could have made more power reliably from such a setup, why didn't Honda just manufacture all of the B18C series to just be a B18B blocks with a VTEC head?