Tuning N/A engines isnt done particularly often, because its comparatively difficult and expensive for the gains achieved, and most folk these days instead simply look at forced induction.
I suspect your B4 will probably have a 12v v6, which is already a pretty poor starting point, and i have to wonder if it wouldnt be a better start to swap the engine out for a 30v 2.8 before doing anything to it. It has 196ps out the box against the 170hp of the 12v, and with some good breathing mods your target of 220hp is probably attainable reasonably easily with the 30v engine.
Tuning N/A engines always follows the same general outline though. First off you want to fix the breathing, that means a decent exhaust system, high flow or removed cats and a GOOD exhaust manifold arrangement (ie tubular). On the intake side theres probably not a great deal you can do on these engines given their crazy inlet manifolds. A performance filter might help with breathing at the cost of reduced filtration. If you were really serious then junk the stock inlet and install some throttle bodies on custom manifolds.
Thereafter your into the realms of huge expenditure with headwork and upgraded cams.
Alternatively fit a 1.8T and a suitable turbo and you'll have a better handling car and far more tuning options, or try and find a PES supercharger kit for the 30v engine.
Personally, i'd junk the 2.8 and fit a 1.8T.
