New Magnum heads for 347 with Flow data

skrews said
Yeah Hughes's numbers are "out there" lol along with many others. Seems like everyone in the cylinder head sales game is guilty of pushing inflated BS numbers in my book.
I was in an interesting test years ago. Myself and 2 others ran a flow test on the same head same port. The bench was a Super Flo 1020 with a Brzezinski fixture. Each of us setup a clay radius entry from scratch for our test. Each of us got different numbers (8 cfm difference at peak). My clay adapter flowed the lowest, guess I wont get a job at Hughes or Indy. We then built a .75" plexi inlet which actually had the lowest flow of all. Absolute consistency and repeatability, just low. This head was then tested on another 1020 bench with the plexi inlet which yielded different numbers yet again (higher).
Ever since this experiment I haven't put much stock in comparing flow numbers ie bench racing.

I completely understand. Margin for me is about 4 cfm, that is a same head, same port, same day testing. The numbers were that close. It will always vary a tad but should still be close. Somehow we all get almost identical 318 ,1.88 360 numbers, 906, and magnum flow numbers, within 2-3 cfm.
Ive used lots of clay, and little clay, so far the only diff it makes is if a smoosh it up a little bit above the port floor...it will cure some turbulence, gee...now what was that about a step from the manifold to port floor again? ;)