Wonder if anyone can advise me on this question;

Would fitting an airtec intercooler to my fiesta zetec S 125 without any other mods make any difference to the running/ performance of the car?
cheers folks

This might be an "it depends" question?

There are some cars where an intercooler swap on its own will produce a significant increase, e.g. because the original was ineffective at lowering intake temperature or had a restriction to the airflow. Afaik the ecoboost is not one of them, and an intercooler upgrade would normally be done in conjunction with further tuning.

The Airtec is available in a couple of versions I believe (Stage 1 and Stage 2) priced around £300-350 and I guess you would be looking to add upgraded pipes while you were at it, plus 1-2 hours fitting time. Other makes - e.g. Forge or Mountune (when available) are similarly priced.

Don't know if anyone will have done this and could comment from experience, but I understand in general you might see a small gain and possibly better response. 

A Stage 1 remap would certainly offer a bigger increase (if that is what you're after) for less outlay/work Superchips for instance claim 158bhp , currently on offer for around £265. Have to add the usual warning here about the Mk 7.5 gearbox.

If you need to replace the standard intercooler anyway e.g. because of damage then an upgrade may be worthwhile particularly if considering further mods later, but at around double the price of a standard replacement, I believe.