Is there any engine I can put in my mk6 fiesta 1.4 without changing the loom guys?

Depends if Zetec, Zetecs work on the same looms to some degree but if Duratec then you're pretty stuck.

Loom isn't even the hard part as you'd just take the loom and ecu from the doner, engine and gearbox mounts are the biggest challenge as are Driveshaft fitments, not to mention the whole thing actually fitting in.

Hi cheers for reply I got a zetec se engine in thr car, I can do everything except I have never changed q loom before so was wondering if theres a engine I can stright swap

Puma engine supposedly goes in easily, but it's not immensely powerful, probably a Zetec 2.0 from a Focus, but it's a wider car so you'd need custom driveshafts which are around £800 a pop, pricey game to play,

What size engine is it you have at the moment?

Do you want to do this because you like that Fiesta? would it not be more prudent to get a MK6 ST? they go for pennies these days, better for messing about with too as Disc brakes and better seats etc.