Does anybody know the air intake diameter for my 1.4 mpi?

measure it? :P lol

Thought I may aswell ask before measuring.

Also, I could easily fit an air filter but how would I get the cold air going into it?

Would I have to get lots of pipes and place it in the front next to that air hole behind the grill?

Thought I may aswell ask before measuring.

Also, I could easily fit an air filter but how would I get the cold air going into it?

Would I have to get lots of pipes and place it in the front next to that air hole behind the grill?

Sounds like you are after an induction kit. Make sure whatever you fit, cannot allow water into the engine, expensive mistake, as engines cannot compress water and they go bang big style.