The B20/VTEC is the holy grail of Frankenstein Honda motors (other than K20a/K24 ... ooh) and will DOMINATE a stock B16. You should use the B20 block (get new ARP rod bolts installed for higher RPMs), the B16 trans, and the B16 head. Get an LS/VTEC kit from somewhere like golden eagle for the headgasket and oil lines. Use the B16 ECU, and raise fuel pressure or chip and tune it with Crome. You will run too lean with the B16 ECU on the B20/VTEC motor.