Found one on eBay with the aluminum filter adapter for 70 bucks. Not expecting any gains from it, I'm just trying to accumulate parts for my forced induction build whenever I find them cheap. Ive never really payed attention to the size of the mating surface or bolt pattern that are on the 90mm's. I'm just kindof curious as to if it will bolt up to my cold air intake flange that runs into the fender. I could always use the adapter plate but I'd rather not be sucking in engine compartment air. They should bolt up right? Anyone notice any nice changes once they added their 90mm? I'm running the 78mm BBK throttle intake also. I'm going to have to add the 90mm to my tune using the strategy at first I guess. Bama says I need to pay the 150 for tunes again even though I traded my car and kept the tuner... Whatever. Just wondering about this thing. I've never done this mod on any of my 2V cars.