vw golf mk3 rolling stones

[vdub golf]

Hello my mate owns a vw mk3 golf rolling stones 1.6 8v and i was just wondering if anyone had any tips, the thing that i was thinking of is either changing the engine for 16v or if i cannot get hold of an engine i suggested to put bike carbs on. So i was wondering what anyone else should think i should do to get a bit more performance out of a fantastic car.

thanks