Actual pressure values for ram air Information only

[mark kibort <mkibort@xxxxxxxxxxxxxx>]

As this subject was beaten to death, we all know that
 Ram Air is an important part of  most race cars =

intake system, but there was a lot of hog wash flung =

around by some of the most intellegent of the List.

However, I thought it interesting to find out the =

actual values so that no one would have incorrect =

information regarding Ram air  , so here it goes.

At 160 mph, with a perfectly (100% inlet, which is impossible,
but we will use it anyway)  the ram effects on the intake
system is .45psi.  with most of the best inlets being =

75% efficient, this number goes down to .35psi.  =

(this comes from a basic racing aerodynamic formula =

in any race tuning handbook) =


 (air density lbs/cubic foot  X air flow  feet/second )
_________________________________________
                                288  X  32.2

Now , since the pressure is related to the square of
the velocity, at 80 mph, the best hoped intake pressure
would be .11psi, and with a 75% inlet, it drops to .08psi.

.08 PSI !!! ,  so basically with the best ram , 100% efficient, the =

ram expected is just  1/10th of a psi.     Now, factor
in a turn or a neck down or an indirect  angle of the scoop, and the =

number goes down from there.

One could only guess that a device that produces 1/2 psi
would be a  thing, too good to ignor.   (im not going to say it !!!)

Just food for thought,  since I recieve so many emails throwing out
numbers that just were not in the right ball park.  =


When anyone mentions RAM , now you know the truth
 and not the guess.

Mark Kibort
innovention.org

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