Heh, surely y'all are kidding...
I may not be as old as some of the gentlemen on here but I'm still old enough to be tickled pink to be called "kid".
GTO-relic, thanks so much! It was surprisingly hard to find out this kind of information. I mean, before I screwed up... But I inferred it was no big deal because I definitely saw some people porting into the headbolt hole so bad it was a big window and sometimes not even sleeving it (admittedly, not Pontiacs). I reasoned the headbolt should seal it because the hole is blind and the washer has 100 ft/lbs on it (ARP head bolts). Was a long time before someone pointed out about the gasket not sealing the hole (the FelPro one I'd always used). And then when I sleeved and still had oil I had to start doubting everything. I'll just chalk it up to a sequence of unfortunate events.
Great to be talking about the actual porting again. I know you're not supposed to "port with your eyes" but I don't have a bench so I did basically just that.
My impression is that the E ports are friggin huge looking. I didn't see either the pushrod nor headbolt bulges as "pinches". And I was vaguely aware that a smooth increase in volume is beneficial. That's why I went really light on the pushrod bulge. Not trying to take off anymore than I needed to smooth the wall. Now, again, to my eye the big culprit looked to be the headbolt bulge because that whole wall is steering the charge around to swirl into the port. So I really didn't like the look of that big ol' "speed bump". I wasn't thinking restriction. I was thinking smooth flow.
I also opened up the actual entrance of the ports to the gasket where the as-cast seems to pinch in a little (especially corners) just at the last quarter inch or so.
The only other thing I tried to do was to somewhat "waterfall" the short turn area like in my Jim Hand book. Last of all I did a teensy bit of back-cutting on the valves with a grinding wheel and a hand drill in a vice. I was pretty conservative here as I didn't want to screw anything up. And so, of course, I did a little lapping when the valves were back in just in case.
I didn't try to "shine" the port walls or anything because a) that looked like a lot of work and b) I seemed to understand a slight roughness here helps fuel stay in suspension. It's smoother than the as-cast, for sure. And I got rid of any anomolies I saw.
It's kind of on my list to tidy up the intake. I did the same on the intake (open the port openings where they were offset, get off any flash, smooth the walls a bit). But I'm thinking about those bulges you pointed out, Steve, like #8. I also spent a fair amount of time this winter with a hand piece of sandpaper on the transition of the primary and secondary bore holes on the high side. I noticed that the factory does some really nice smoothing at the bottom of the deep holes on the low side but the high side holes are basically cylinders. I've been trying to smooth a radius onto these. And I'm also thinking of trimming the ends off my carb mounting ARP studs that poke through into the upper plenum about a quarter inch or so. Not sure if any of this helps. I bet the radiusing I'm doing will help the most..
Really thankful for all the help, folks!
Sam