First off... wrong forum...
The B16 is in the car already? Hands down the best bang for your buck engine-wise is cams and tuning, then go ahead with the IHE and stuff.
I would spend the money on suspension first, since you probably aren't putting down all your power as it is now. Suspension helps the car in every way: prevents squat and dive, improves cornering and handling in general, and looks better.