No, he means a 4 barrell intake manifold for the slant six. They are available from many sources, Mopar, Mancini racing, probably Year One too. I had such a set up on a '66 slant six Dart...not an original Hyper Pak, but a JC Whittney catalog order. Just the intake, small 4 barrell and still single exhaust and it woke it up a lot! No change in the bottom end of motor at all. I'd start with that, then build on. They make a header for the slant six which I would advise doing at the same time to maximize your efforts.