David Vizard, Uncle Tony's garage, Unity motorsport. Mission impossible Dodge 302 Head porting

273 said

A port don't flow 195 cfm's on the engine, that just telling you how restrictive that port is even if the engine displaces 800 cfm which is like a 460 peaking at 6000 ish rpm that only a 100 cfm's a cylinder but your gonna need a fairly big port and a lot of cfm @ 28" for a 460@ 6000 rpm even though the engines only displacing 800 cfm

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That's not even close to reality. The engine damn sure is using it. Even a cam with 250°@.050 is only giving each cylinder .007 seconds each cycle (at 6K)to fill with an actual 100cu.ft./min., that means the flow has to AVERAGE that amount of flow thru' the lift cycles, peak-lift flow numbers are not the definition of a good port. Tuned-length runners, excellent mid-lift numbers, & good port velo are more important in conjunction with the right cam utilizing the overlap. Once You've reached that head's limits, no matter how good, it's done. The "arguing" is just, should one whittle & work away at an efficient head with a lower ceiling, or just jump to a better head without all the hard work at a slightly lower efficiency.
The AVERAGE enthusiast usually prefers the latter, because it's more cost effective in reality, & more reliable in it's results.