The machine shop said the one combustion chamber is rusted too much to clean up. One guide cracked when they pulled the valves out though I drilled most of it out and it drove right out after I left maybe 1/16” of wall thickness. I’ve found two heads around here that seem to be ok, I’ll see how it goes when I dig into them. As a bonus they come with the rest of the engines, though I don’t really need all of that. But one thing seems odd, I see heads with 235 casting numbers put on 261 engines with the extra water holes, and I’ve seen this more than once. Did GM Canada use 235 castings and drill their own extra holes for their 261?
