Moper and Ramcharger,
This is why I like the small runner heads that have been opened up to the larger runners of a fairly large intake like the M-1 or the super victor, then taper them down to the smaller valves and this keeps the velocity up and the air/fuel charge moving. Creating a ram effect and it produces very good Tq. and very good HP through the range. This way you can get away with the smaller valves and smaller ports, and they will make power like the larger ports of say a 360 head.
Interesting that you mention this as every text I've read states that the ideal shape is a gradual "funnel" if you will towards the valve rather than a straight cylinder. I assume from what I've read that this will increase the speed of the air/fuel charge as it nears the turn and the restriction of the valve itself. Would this be to "even out" the velocity of the mixture at the short turn from the naturally higher velocity of the charge running along the port roof thereby somewhat negating what would be an uneven charge flowing across the underside of the valve?
From my experiences the heads being done this way pull vary hard up to about 6,200 rpm's with 318/302 castings and up to 7,000 with the 360 castings with the 1.88 intake valves. After 7,000 rpm range I then use the 2.02 valves. But correct me if I'm wrong but the larger 2.02 valve heads tend to lose low rpm Tq and HP, thus the need for loose converters and steep gears.
I'm in no position to correct you or anyone else since I don't have a flow bench, lol! If this is what you've seen and done, that's great stuff. I will say that I when I had my heads milled and the valve job done and hardened seats installed, I just had them stick some 2.02 Ferrera's in there since I got them way cheap and the valves had to be replaced anyway. They did zero throat, bowl or port work and when they installed the guides, they left all kinds of metal splinters sticking out from the guide boss. I thought that they would at least clean that up. They did a lousy job all in all including leaving lapping compound on the back side of the valves and and not seating the springs correctly on the retainers.
Anyway, after dissasembling the heads I did smooth out the throats, re-profiled the short turns and smoothed out the guide bosses as well as gasket matched about 1.5 inches into the port. I have no way of knowing what improvements I made if any but this engine runs very strong with a mild cam and 1.6 ratio Crane rockers (Lunati Voodoo 60401, Duration @ .050 (Int/Exh): 213/220 Gross Valve Lift (Int/Exh): .454/.475 & a 112 LCA) Far stronger than it should in such a heavy vehicle at this altitude.
Another thing that I noticed is that I have to run it quite a bit richer (74s in the primaries, plugs still look a little lean) than i expected at this altitude and also had to go up 2 sizes on the squirter (.024 to .032). I suspect that this may be due to the valve size being larger thus requiring more fuel to do the same amount of work due too to low of intake/port velocity. Or, the larger valve may be compensating for the lack of air here and that's why i have to jet like I would if i was back in Chicago.
Also too when flowing a cylinder head you really should have the intake manifold that is going to be used also attached to the head so the flow and or modifications can be made in real world circumstances.
This makes perfect sense.
The only other effect that will be but cannot be accounted for is varying air pressures and changing corrected altitude's (Baro readings), and density. Which this has a direct effect on how the heads and air moves through the engine and it's ability to perform properly. This will also change the wave or pulse of the port/intake, thus the need for leaning or richening the carb, or fuel system.