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Old 09-25-2009, 08:44 PM   #54 (permalink)
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Moderate your Moderation.
 
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Quote:
Originally Posted by mcmahon.craig View Post
Anyone here ever measured the EGT drop across the turbine wheel in the turbocharger? I'd always thought they ran mostly on exhaust pressure, rather than heat.

In my own personal experience, all I know is that the turbo is still stupid-hot while running. None of the other (downstream) exhaust components on turbocharged cars ever seemed especially cooler either(ie, still enough to suntan my face).

I DO know that a pound of gasoline contains some 20,000BTU and the engine loses about 9000 of them out the exhaust. Seems like there's room for improvement.
Heat from combustion is what actually creates the pressure, so either could be used to quantify the extraction of energy from the exhaust.
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