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I mentioned this in another post and was requested to post it here. it is a break down on how much enery is used or lost durring normal driving. This was done on a european car with 4 cylenders, manual, rear wheel drive.
35.3% exhaust heat
30% engine heat
8.5% internal friction
4.2% charging change
6.9% air resistance
4.0% rolling resistance
6.4% translation losses (acceleration)
0.6% rotary losses (acceleration)
0.3% axels
0.9% transmission
0.4% clutch losses
1.5% alternator
1.0% power steering pump

for all you power nuts out there I though this might be interresting.
 

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I'm confuzzed...

is this a calculation of what percentage of the total power loss is attributed to these factors?

like if you're down 10 HP.. 3.53HP is due to Exhaust Heat?
 

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I think it's supposed to mean where the energy in each drop of gasoline goes. It's a known fact that an Otto cycle engine is only about 25% efficient, and this study does show that. (100%-35.3-30-8.5-4.2)=22% that actually gets turned into power.

The rest is resistance to moving the car.

Problem here is, there aren't many stats on what this car is. Weight, acceleration, etc... So that's kinda useless.

I guess it does give you an idea where the power goes.
 
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