B20 or B18? VTEC?

okay i can get a B20 form a 1998 CRV for a very good price.
i still have my B16 head.
now what is best?
keep my B18?
B16 head on B20?
B16 head on B18?
or even B18 with B20 parts?
what can i do here to make some power?
i still have my B16 head.
now what is best?
keep my B18?
B16 head on B20?
B16 head on B18?
or even B18 with B20 parts?
what can i do here to make some power?