Airwolf

my friend has an 86 CRX, the body and interior are nice but it has over 250k miles and it has had a lot of problems. He said hed sell it to me for 200 bucks, and if i could put like a ZC SOHC or something, it would turn out to be under $1k for a nice car. But what i wasnt sure of, was that doesnt the motor year have to be the same as the car to be smog legal in california? Like could i buy a b16a1 or a d15b vtec and put it in? or would the zc even go? any help on what motors i can put in this 86 crx would be greatly appreciated, thank u soo much.