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      09-08-2009, 07:05 PM   #59
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Quote:
Originally Posted by GreenPlease View Post
FWIW 14psi doesn't necessarily equal 14psi when it comes to making power. 14psi at 150f is a lot less dense (and therefore contains less oxygen) than 14psi at 100f.

N=PV/RT where N=moles

Scenario 1
AIT:150f
Pressure: 14psi
Volume: .5liter (one of our cylinders)
Result: .0171

Scenario 2
AIT: 100F
Pressure: 14psi
Volume: .5liter
Result: .0186 moles

By lowering AITs in the second scenario (an aftermarket intercooler) the amount of oxygen available increases by 8.7%, thus power output should increase accordingly. If the car was making 300whp prior to the aftermarket IC, then post aftermarket IC it should make ~326whp. Additional gains may come from less restriction in the intercooler resulting in reduced pumping losses.
Are we using the Ideal Gas Law for describing O2 density in a boosted situation? The Ideal Gas Law assumes an incompressible fluid and which is clearly not the case here. I am not arguing more O2 will enter the cylinders, but not anywhere near enough to justify 43 rwhp. Lastly, you cannot use percent increase in O2 to determine power increase. If you logic was indeed true, then doubling the CFMs from the turbo should double the power from 400 rwhp to 800 rwhp.

Take this for what you will, but run I am sure Eric will agree that if you run identical boost curves then you will know what is the AMS intercooler flow and what is common to any aftermarket intercooler. In an ideal world this is exactly what would be done, but in a world of forums and marketing this unfortunately doesn't exist. The only way to know anything is to bench flow the intercooler, log efficiency, log thermal heat capacity, etc. I haven't seen this data, so we have nothing really to go on. Look, I am just like the rest of you guys... I want the best and it seems that sometimes is nearly impossible to determine.
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