I got a friend of mine who just put in a D16a6 in his 91 Civic STD. Hes got pretty much eveything in and ready to go, except for this "thing" that goes on the back of the intake manifold. We dont know what goes in this spot. All we know is that a thick black hose that runs from the brake booster to this spot on the intake... so we know it has something to do with the vacume. If anyone knows what goes in the spot in the picture above, please let me know. Where could I get this "mystery peice" at? Thanks for the help, it is greatly appereceated.

P.S. I am talking about the 3 holes in the pic. Looks kinda like this---> o0o