damaged head stud threads

I started putting my heads back onto my motor today. last year in august I pushed the head gasket out of number 2, cracked the head. I had the head welded and machined. put it back together for one race then ended the season.

today, when I began installing the head, as I began torqueing the head down, I found that the threads in the block for the head stud above number 4 cylinder have been damaged and stripped out.

what is the best way to repair this? helicoil? I have never installed one or come across this sort of thing on such an important stud.

I have read that in McMaster carr part number 90248A034 would be a good way to go. can anyone help?

also, is it possible this happened during the explosion when we blew the head up on number 2 cylander last year? or did I damage this myself somehow installing this wrong? the block was decked and removed .08 off the top this past December also. thanks guys

 

I have a kit I think I got from Keith Black that has a modified TimeCert, long drill and TimeCert tap. Might check with them.