I bought a set of ported 915 B/RB castings a few years ago from a fella on MOPARTS, claimed they are MM ported, makes no difference, they are ported but I can't tell you anything other than that! They do need some cosmetic cleaning and a valve job. They come with a new (in-the-box) set of Ferrea 5000 series 2.14/1.81 valves, nothing else...$450 plus shipping. PM me if interested, thanks!