my 2.0 zetec made 155bhp with a mapped unichip with roughly the same mods (mine had a standard head though), but that is the limit of the injectors. the tuner said if i had got bigger injectors at the time it would have been around 165-170bhp.

i ended up going for a supercharger conversion after that which came with bigger injectors so i dont know what it would have made.

i can confirm the superchips are shite on the zetec engine.

you must get it mapped ASAP if you are running performance cams or it will be running very very lean, mine was (but i only ran it like that for a few weeks below 3k rpm's while i saved up!). mine was 20bhp down on power because it was so massively lean with no fuel pressure increase on the standard ecu! so it had totally cancelled itself out power-wise and was drinking fuel galore.

other options are megaquirt but they are a bitch to wire in if you arent an expert, or you can get the standard ecu remapped at alot of places now, or get Omex (but its £1200 ish and would be overkill for your setup)

fit a bigger throttle body, that helped on mine, and induction kits do work good on them if you fit cold air feeds and fit a decent size cone. they arent that noisey TBH.

avoid the K&N 57i, it is totally over priced.

other bolt-ons you can do is underdrive pulleys, bigger bore MAF, better inlet manifold, adjustable cam gears, and a lightened flywheel.