How do you repair a cracked head gasket on a 1994 Dodge Intrepid DOHC 3.5 L?

Replace the head is the proper way. I had an Intrepid that the customer didn't want to spend the money on repairing it correctly and we put a product called Irontight (from Carquest) in it. When used properly as the instruction tell you it sealed up the leak that was so bad the coolant was hitting the firewall in a steady stream. It's been 8-10 months and I still see the car (a neighbour) and it still holds coolant without any leaks. Don't know what it does to the rest of the engine components but no leaks yet.