while under my brick this past week replacing the header and cat I noticed a port on the passenger's side of the block, pretty far back toward the bell housing and not visible from above. this port is of the sort that a soft hose would normally fit onto (presumably), made of what looks like brass and having a stepped slightly conical shape (as to grip a rubber line). this port looks as thogh nothing has ever been attached to it and I am at a loss as to what it does. the car runs great...and now sounds normal... header pipe without gapeing hole. My only guess is that this port was for an external oil cooler? if so, why isn't it plugged? any idea what this item does?