porting heads question

You will probably want to get some grinding stones on a 1/4" shank. But you will need an assortment of cartridge rolls in diffeernt shapes and grits. Summit sells there own brand for a fair price, and it comes with the 1/4" arbor for the cartridge rolls. As for the burrs, Ebay has some pretty good prices, on what you need. I like the 4" long shanked burrs, they are long enough to do most of the port and not too long to bend easy.