Tuning 2.0 Zetec Focus?

Looking to do some things with my car, as described above.

I want to fit a full induction kit and stainless exhaust system, possibly a fast-road cam, but was wondering what effect this will have on the mapping of the ECU, and therefore, whether to have it all done and the engine chipped at the same time, or if I can do it a bit at a time?
The induction kit and exhaust are best done together to get the best effect. Normally you shouldn't need to do anything to the EMU as the sensors should automatically adjust the settings. Basically using these two modifications you make the engine run leaner so the EMU adjusts the fuel flow meaing more bang on each power stroke. You could find this alone gives upto a 15% increase in power but at the loss of fuel economy and increased emissions (possible MOT problems).

The Zetec engine is a good strong engine which has proved itself capable of some serious modifications, just look through a selection of tuning mags to get an idea of what is possible.

For more advanced modifications I would suggest speaking to a specialist company. Things like camshafts, pistons, undersized drive shaft cogs and the like may need the chip remapping on a rolling road to get the best out of them. You may have to decide if you want full on balls out power or sacrifice a little top end to keep it drivable around town. Oh and you will need to invest in an aftermarket chip for the EMU as the factory one is preset and can not be adjusted.

Finally speak to your insurance company about your plans. Most will drop you like a hot potato as soon as you change anything but some will be OK as long as you tell them upfront. You will find your premium goes up as you are changing the car from standard (even changing the standard brake pads can be enough to have problems).

Good luck and have fun with it.

ps ignore the 8 cylinder idiots, when did you last see a V8 rally car??
I say save your money, it isnt worth it on a 2 litre focus !

Buy something with a lot more poke !!
you want us to tell you to experiment with your car.yea, go ahead. do it,.no balls no glory.every journey begins with the first step.and so on and so forth.
now that you can overrev the engine and squeel tires you can't figure why the engine blew up. DUH! BUILD A REAL CAR. UNO, .ONE WITH 8 CYLINDERS OR MORE! OTHERWISE YOU ARE A WANNA BEE!
Well If you put only a exhaust , you dont need engine management. If you go turbo or supercharged you should and cams you should get a engine management to control the ECU, becuase without EM the car wont run to its max and detonation can be a problem. Also you will need some bigger fuel injectors and fuel regulator.
The first and I mean the VERY FIRST thing you should do is uprate the brakes. If you get it to go quicker you need to be able to stop quickly as well. Other than that the easiest is to get a garage to fit a raced tuned engine, everything will then have been done. Check out "Fast Ford" magazine!
ask your ford dealer.