Thread: DIY Flow Bench
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camgrinder camgrinder is offline
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Join Date: Feb 2004
Location: California
Posts: 921
The problem I have seen only shows up in 2 or 3 heads out of 100. Usually it can be fixed with some attention to the short turn radius.
Its my belief the higher velocity seen at the higher pressure drop
can cause the air detach from the boundry layer and tumble.
The interesting thing is at higher valve lift the flow comes back in line.
I have a 2 freinds with the SF110 flowbench. When they see a slight oscillation on the manometer on thier bench (@ 10"), and I test the same head on my SF600 (@ 28") the oscillations are dramitically multiplied.
FWIW My bench calibrates within .2 % of the setting when it left Superflow in '92. I have also tested an orifice plate on mine and 2 other SF600 benches in the SF Bay area and all 3 benches were within 1%. Flowbenches are like chassis dynos... They are best when compared against themselves and not compared to a bench or a dyno 1000 miles away.
John Dougherty
Dougherty Racing Cams
Old 03-28-2005, 05:31 PM
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