318i m40 tweaking

[E30_Don]

I'm trying to get a bit more oomph out of my 89 318i, its a nice car and insurance wont allow a 320is yet.. So i was wondering if theres anything i can do, ie chipping?? has anyone done this to theirs and was it worth it, already got an induction kit, does anyone manufacture 4branches and stainless systems for these??
cheers

[smithy318i]

Zone chip mate.
The standard airbox is the best too. None of this K&N shyte.