I think bullit was sayin no to the 16v question not ur response mate
And yeah theyre 75bhp std at the fly, prob a bit less after the years. Breather mods are the way forward, sort out a decent panel filter or enclosed induction kit, stright through exhuast system and a 4-2-1 manifold and youll be close.
Its not a great engine for tuning though tbh, if you can afford the insurance declaring all the mods if you plan to insire them, you may aswell whack a VTR lump in there. Unless you just like to tune it anyway, which is a better view than just going for power i reckon