em ported means u go get a steel brush kit for a drill and stones for gringing,take 1-2mm off the entry holes for the manifold,when u take it off ull see the 3rd hole has a big lump which is a bolt cover,grind it away till smooth like the rest.then u use brushes to pollish.when done all round each hole the hole will be 2mm larger all round
this lets air flow better and more easily.
i use alot of hks,speed vision,there are alot of traders on here and there best for things
dont use ebay for things as they are badly made usually