I used MIG. I was told by some that said to use a high nickel content rod because it is cast iron. But I had a welder look at it and said that it was cast steel. He told me that I can use a regular MIG (just preheat cast, it will hold fine for what I am putting in front of it (400hp small block). He did tell me that the nickel rod would be better but not a necessity with cast steel. It welded, really no differently.
