K&N suggests the use of "sealing grease" when installing any of their filters. This grease stays thick even when subjected to heat. In the case of the DeLorean, use of the grease does, in fact, pretty well seal the area around the filter, making up for it being just a tad undersized. This, in addition to using the brackets from the mid-state club, should preclude dirt getting through. I am currently using this set-up and have not noticed any unusual build-up on the throttle body plate. Dick Ryan VIN 16867 __________________________________________________ Do You Yahoo!? Get personalized email addresses from Yahoo! Mail - only $35 a year! http://personal.mail.yahoo.com/