welcome by the way
1, from what i gather, an 8v is revvyer if thats a word, but all things concidered if its got more valves then its a faster engine, itll make you to higher speeds and itll do it quicker than an 8v, i was recently told that the 8v injection system wasnt as good as the 16v one too, but that might not be true, im certainly no expert
2, on a pre 90 spec youll have small bumpers, your electrics are different,the popular example is your hazard light switch, on a pre90 its a switch on the dash and on the 90 spec its behind the steering wheel, on a post 90 youll have arches which join to sill extensions which all go nicely with the bigger bumpers that they have, they are also a fair bit lower, i think by 20mm but im not sure, you get a load of that stuff on some 8vs known as run out editions or something like that,
theres a whole load of other stuff im sure,thats all ive remembered since posting here, be prepared for some far more detailed posts on the subject ide have thought, or just run a few searches and youll find near enuf any question you might have has been answered at some stage or another, have fiun mate