the HKS mas adapter came today. the filter i had will not fit. the adapter is 4" and the filter is only 3." anybody know where i can get a filter that will fit (asap) or a 3 to 4" rubber coupler? thanks a lot.

Get a rubber sewer pipe adaptor from Home Depot. I used them for my I/C pipes and the intake plumbing before the turbo. Cheap to boot. They should have a 3" -4" piece.

does anybody make a 4" filter?

I have one. Go to advance auto and look through the K&N book. They make every size of filter you could think of. They'll order any of them