just a quick query ... just ordered my new ford fiesta zetec s tdci (would have had the st but have to think about economy) does any one know if the 1.6 tdci is the same as is in the focus and c max ... if so i have noticed that the focus bhp is 110 and the cmax is 115 so in theory the fiesta tdci unit could put out 115 bhp without effecting reliability would it be a matter of the way the ecu is mapped or would it be down to engine components any help would be appreciated thanks marc

It is the same engine. I believe the reason it is de-tuned from cmax / focus power is gearbox reliability; i believe the intial plan was to have it around the 100bhp mark (i.e similar to the petrol zetec-s), but the drive train wasnt quite up to it......

That's right, the C-Max has the stronger 6-speed box. The 5-speed can't cope with the full torque so the engine has been detuned. As a result I would say make sure you know the mechanical limits of what you're dealing with prior to chipping the engine. I personally would investigate where else the gearbox is used.

Id just leave the Zetec S as it is my friend, its a very nice car with a very well set up engine.

When you start fiddling with the engine management you will start creating you self problems which in many cases wares parts out quicker and can lead to being very expencive...

As they say... dont fix what doesn't need fixing. Ford have done it for a reason so leave it that way!

Hope you enjoy your new car and i hope you will stick with us on the forum as your input would be really great to have as we dont have many Zetec S owners.