Heres a better start for you, the 1.2 8v camshafts are pathetic, the lift and duration is terrible. Fit a camshaft from a Nova 1.3 SR or the GSI, GTE and you can see an increase of about 4-5BHP (this is proven by the way, not just internet crap) The next thing i would do is fit a free flowing full exhaust system from the manifold back, decat would be even better but you need the cat to get through the MOT, backbox alone wont do anything. A shielded induction kit or modified airbox would also help throttle reponse and slightly up the power output.
If deathcythe was still around im sure he could help too, with his fuel pressure regulator mods etc etc.