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Horsepower in relation to cfm, engine displacement, and a few others

  1. Jan 1, 2009 #1
    Hey everyone, this is my first post.

    A short while ago I came across web-calculator that calculated some theoretical horsepower based on values you entered. The values were CFM (amount of air flow) atmospheric pressure based on a barometer reading (you could choose either inches mercury or water) the CID, or displacement of the engine and the number of cylinders.

    You put those in, and it popped out horsepower and theoretical peak RPM.

    My problem is I cant for the life of me figure out the relation between those variables. All of the equations I have found take something like the VE and the compression ratio of the engine, some other random values, and actually do not include CFM at all (which doesnt help me)

    Ive tried only varying only one value at a time and making some tables/graphs in excel, but I end up just getting overwhelmed and confused.

    Any thoughts?
  2. jcsd
  3. Jan 2, 2009 #2

    Ranger Mike

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    Gold Member

    welcome to the world of IC...I found the best source to satisfy my thirst for knowledge about the Internal Combustion Engine is the book...Elements of Internal-Combustion Engines by A.R. Rogowski, S.M. published by McGraw-Hill Book Company..it was printed in 1953
    hey..it is old but printed same year as I was born...covers EVERYTHING..Gas laws, forms of energy Air cylce, fuel air approximations, engine vaiables on flame speed, engine friction, detonation, air capacity...everything but the smog junk we have to add now..parasitic waste of energy..IMHO....until big something , is invented or introduced to the consumer public, we will be fossil fuel dependant for the next 50 years because nothing, repeat NOTHING has come along that is economical enough to replace fossil fuel, that is acceptable to the world market place....i been thru this drill in 1972..first oil embargo..was still in college..everyo ne was going to go GREEN..the IC was presummed dead...the only thing that happened was the death of big cube engines..Hemi, 455 Olds, 460 cube Ford...

    until a new power source happens, the IC will be king..maybe diesel a close second like it is in Europe but ..for the next generation..still is the IC.
  4. Jan 4, 2009 #3
    Thank you very much for the reply and the information! I'll definetily be looking into that book. Thanks again.
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