sr20 would be a waste of time. If you wanted decent power out of it, it would be as "unreliable" as a rotary. Not to mention all the extra monies you\'d spend getting it in there.
V8 swap would be good, though the only one ive seen had a lot of extra work, it was by no means an easy swap. TBH the only engine id bother with is a detuned v8. Maybe a JZ but meh, might as well go v8