Your results will be uncertain, 3DDave has probably a good a reference from a manufacturer as possible, but even so, that source is "farm and tool shed qualified."
Welding cast iron to cast iron is hard enough. Welding cast iron to carbon steel is harder yet. Just as there are many grades of carbon steel, there are many grades of cast iron.
My best success welding cast iron is with an oxy-acetylene torch and cast iron rod. High preheat is a must, and the interpass temperature has to be maintained during the entire welding cycle.
The application must also be considered. Is the weldment subject to thermal cycling? There is no cookie cutter answer.
