16bhp sounds optimistic but i can believe it... do superchips not do a chip for it?
as paddy said if you fancy a turbo fitting an RST lump would be the easiest way.. although thats not for the faint hearted on a KA...
the 1.6 8v duratec is just a bored out 1300... van aarken do one for the 1300 - unless thats only for the old pushrod one and not the 1.3 duratec i don't know...
the sportKA is a class little car to drive - great gearbox, do you get frustrated with it topping out at 110?