I had a 1.6 Zetec for 4 years, It's a brilliant engine. I would reccomend fitting a 1.8 throttle body and a performance panel filter, I like pipercross myself. I had mine on a dyno and had a 96bhp reading, the engine has 89 as standard, the car had 107k on the clock and a magnex back box at the time, I later fitted a full magnex stainless steel cat back exhaust which no doubt would have improved slightly. Make sure the throttle body is clean and polished on the plate and spindle, Ignore the instruction to not clean it, the difference in smoothness and response from the engine is fantastic. Don't bother with the air flow meter as it just confuses the engine and runs like a bag of nails, others say it works but I disagree. I would guess that their air flow meters were faulty and the car just thouight it was disconnected which will allow the car to appear to run ok.. The above mods which I did will see you right but you will never get major performance from this engine.