Since there are six individual air inlets, you have to place it in an area of air just before it goes into the trumpets. If we were running plenum chambers like a 280ZX manifold, then yes, you screw it into that. If you thread it into just one runner on the manifold, it (the ECU) will base the fuel map on the running of that one cylinder. In the air stream in front of all six, will be a better average.