Jim Wolf Technology POP Charger (specifically for the 300zx MAF)
These are known for the power adding properties. By utilizing a special venturi inlet, it aids in adding power. It features a reusable/oilable low restriction air filter element as well. BONUS part is that if you are running a 300zx MAF, now you have the solution to the forever going problem - where to find a MAF adaptor plate... This kit includes the adaptor with built in venturi, clamp, bolts, and air filter.
JGY price: $110