Steel to Cast with mig repair

[doubleboost]

The weld looks very good
Depends on the grade of cast iron
I have pre heated used the propper rods cooled slowly and the job still cracked
I prefer brazing now for cast repairs
I once mig welded a exhaust manifold in position it was very hot from the engine running , as soon as it was welded we started the engine up in an attempt to cool it slowly
As far as i am aware it is still good
John