well to give you an idea of figures:
1.6 Driver - 75bhp (there or there abouts)
1.8 Driver - 90 bhp
1.8 8v GTI 112bhp
I had a 1.8 driver engine in my scirocco, it picked up well with the scirocco being quite light but never set the world alight and ran out of puff at about 5000 rpm (a GTI cam would fix that prob though

) , my old 8v mark 2 gti would eat it for breakfast though I think.
having said that it would feel quick compared to a 1.3 (if i am right in thinking thats what you have at the moment

)