bout to change the intake but all i know so far is that i need to put an adapter on the mass air and i just need to know the size 3 or 4 in and will i need to put a filter on the air compresser cuz the hose will lead to nothing wen i take out the old filter box

n/a 87

 

Yes, you should put a breather filter on the air pump. As far as the inlet size on the adapter, I have no idea, I've always had S5s. I'm guessing if you search, you should find it.

 

A 3" coupler will fit on the S4 AFM.

 

I have the adapter (new never used), if you need it. I'll PM you.