Head repair
Head repair I have a set of 643 casting heads that I ported/polished on a flow bench and ran for 6 months with no issues. The engine was pulled and sat on an engine stand for 2 months. Upon first start up the #2 exhaust port is leaking coolant. I took the header off and pressurized the cooling system and it appears to be leaking from where I circled in the picture. Its at the machine shop awaiting inspection but I just wanted to see if anyone else has had experience getting a crack repaired in the same area to see what my chances are. The machinist doesn't like my chances but he also told my porting and polishing is useless so he may not be familiar with this head casting.
Aluminum can be TIG'd just have to find someone that knows what they are doing. Far as your port work I would say "it depends" does the guy think porting GM heads is a waste? or was he commenting specifically on your work? If he thinks GM heads are a wasted effort then he is clueless, if it was your work he was commenting on could go either way.
He was saying because of the location it can't be fixed. He was saying gm heads in general and that the only way to go is cnc. Cnc is better obviously but I know for a fact porting and polishing yields results... maybe I need to find a different machine shop.
