-> OEM uses less than that, there is no real flow, just enough vol. to -> move diapharm, some have a small vac leak, but not much. I'd noticed most of the OEM setups seem to use those teeny hard plastic lines, ID probably less than 1/16". Would 1/4" OD lines be sufficient to handle EGR requirements? I don't have any figures for how much volume EGR requires.