CFM flow vs. RPM calculator help

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Oct 28, 2003 | 11:07 AM

bnoon

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From: West Des Moines, IA

Car: 2008.5 Mazdaspeed 3 GT

Engine: 2.3 DISI Turbo

Transmission: 6 speed MT

CFM flow vs. RPM calculator help

I used to have the calculations, but they seem to have disappeared from my PC here. Does anyone have the airflow calculations handy for port design, intake flow, etc. for CFM vs. HP potential?

Oct 28, 2003 | 11:12 AM

fireturd350

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From: New Boston, IL, USA

Car: '90 Formula 350

Engine: 383 SBC

Transmission: ProBuilt S/S 700-R4 & ACT 9" Stall

Axle/Gears: 10 bolt 3.23

You mean like: CFM = (CID * RPM * VE)/3456

http://www.fortunecity.com/rivendell..._calc/cfm.html

Also:
HorsePower (per Cylinder @ air flow) = 0.43 * (Head flow CFM @ 10in-h20)
or 3.44 * CFM for an 8-cylinder engine.

Example: At .500 lift a stock "C" head flows 250 cfm at 28" of H2O. You must convert this to 10" of H2O. Click HERE to find the correct multiplier. The potential HP is (.598*250) = 149.5 * 3.44 = 514 HP

http://www.angelfire.com/wa2/Olds/headflow.htm

Or maybe:

Interactive Engine HP/RPM Computation

http://www.bgsoflex.com/flowcalc1.html