first of all...you already have a ls! why would you spend more money and get a gsr? unless your rich yea go ahead..anyways if i was you i would keep the ls and slap a b16 head on it.
go with the gsr because ls/vtec doesnt work
thats because the moron you know or seen that build his doesnt know how to. to succesfully build a ls-vtec that is "reliable" you need to swichout the rods and pistons. shit alteast the rods. hope this helps.