http://www.eternaltools.com/blog/7-facts-about-tungsten-carbide-burs-and-how-to-use-them

I don't have many answers for you. Never ported anything iron.

Used an assortment of burrs on my intake manifold and air grinders.


-Dustin
67 Dart, 9 second, 392" G3 Hemi
68 Barracuda 340 F/SA