The margins aren't that wide on the head, maybe about .05", seemed like a standard contact width to me. It's a single angle cut, ran out of time to do a multi-angle job. The machinist really wanted to do a 3-angle job on them, but between the rough shape of the valves and the time limitation I imposed on him, he was limited to a stock single 45* cut. Three of the intake valves he absolutely did not like the look of, but new valves are either pricey NOS or full custom, and I already have spent more than I wanted too plus again the time constraint.
The guides on the intakes apparently had been replaced before and he said he didn't see any reason to replace any of the guides and that I was using the wrong type of valve stem seal on the intakes.
I'm going to make the sheet metal intake on this engine so I can be sure it clear's everything like the wiper motor. I am changing up how I was going about it though, originally I was going to use simple exhaust tubing, but now I'm going to take a 2x4 and shave it down with the proper taper and bend and hammer sheet metal around it. It should get me a consistently shaped runner that is rectangular like the port. My air flow buddy is ready to make me an aluminum intake, but had to tell him he was putting the cart before the horse because I need to know it clears everything. So I may take him up on his offer when I have a functional intake that clears everything and ready to spend the money.
I agree with you Tom on the exhaust ports, I'm not going to go all out on the bottoms.
Rebuilding an OHC Pontiac 250 with EFI and a Turbo