Math Formula Support Page

How to reach our numbers!

What If Dyno



Project Goal

Issues needing resolution

O2 Sensor Theory

Combustion Dynamics

Detonation Effects

Supporting Math

Progress Report

Testing Procedures

Political Rant

Click images for larger

Fan Shroud

Beginning of engine stand

Stock ignition w/marks

Valve lapping with hot glue
preheat bolt and valve with
propane torch, use tubing
and drill after cooled.



If you find any mistakes here, please let us know.

Engine air intake Flow meter Supporting Math

1. piston displacement = pie*r*r*h = 3.14*1.5*1.5*2 = 14.1 cubic-inch per piston

2. 4-stroke engine intake cu-ft/min = cid*3000/12/12/12/2 = 28.2*3000/12/12/12/2 = 24.479 cubic-feet per minute. With breathing effeciency of 85%, 0.85*24.479 = 20.80 cu-ft/min

3. one-inch diameter intake port has (3.14*.5*.5)/12/12 = 0.005451 sq/ft of area.

4. flow cu-ft/sec-cube = area sq-ft * Velocity ft/sec


Velocity ft/sec = flow rate (cu-ft/sec-cube) divided by (area sq/ft)

V = 20.8 / 0.005451 = 3815 ft/min

5. Average intake flow rate conversions - 3815 ft/min = 3815/60 ft/sec = 63.59 ft/sec
       = 21 meter/sec = 43 MPH

6. Peak air slugs will be much greater. We will try to using a handheld anemometer mounted in the air intake duct work, but the peak air flow slugs may exceed its capability.

If you wish to help this project grow with one dollar or more ........ Thanks for your support!
These donations will be processed by NEFCON and used for test engine stand and circuit board prototype expenses.

If you would like to provide additional information or recommend suggestions for this co-op project, or join this co-op project,
contact Lynn and let him know what you would like to contribute.

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