Quote:
Originally Posted by swamp2
Isn't even the first part of this claim a bit irrelevant since all modern FI (and NA) systems adjust for temperature? I don't know if they adjust for humidity but I think that is a 2nd order effect compared to both temp and altitude.
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As per the norm for us, we're talking apples and oranges here.
Of course they all adjust for temp, pressure and humidity, but the SAE says (in standard J1349) that a forced induction engine gains and loses proportionately more when it does so in response to those conditions. Increased temperature, for instance, may lead to more aggressive spark retard (and possible reduction of boost in turbo engines) than would be the case with a normally aspirated engine. So, when a manufacturer puts a test engine on a stand to test for SAE Certified power, they are allowed a greater "adjustment" with forced induction to get to SAE Net standards when the air inlet temp is, say, 100 degrees F (SAE standard is 70something degrees). So, 100 HP observed may become, say, 110 adjusted in a normally aspirated engine under whatever hot/humid conditions, and 111 or 112 in a forced induction motor under those same conditions.
In other words, footie is correct.
Bruce