search LS/Vtec or some variation of that. the swap has been done many times with the newer gen guys. there is quite a bit of conflicting info on this site about it (search, lots of info in this site) apparently some guys love it, lots of power. i believe the Vtec head is comparable to the B18 head in design aside from the Vtec technology. from what i have read there is no issue with C/R or anything like that. while some guys love it others hate it with a passion, i read an entire (somewhat of a rant but quite educated) post about the con rod length in relation to the stroke i think. anyhow, the B18 block is not designed to take the power that the B16 head produces and it's a ticking time bomb to put a rod through the block. like i said, search and you shall find. as far as swapping a b- series into a 84-87, there is a mounting kit but every post i have ever read on the topic has at least one person pointing out the $3000+ price tag in the long run. i myself have never priced it out (i have a 2G, whole different story) but it sounds as though it's a pretty close figure even if you do come about a free motor.
mod eh... hmm