At 18.26 2012.03.30, you wrote:
>
>
>> -----Original Message-----
>> From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf
>> Of Sean Breheny
>> Sent: 30 March 2012 16:56
>> To: Microcontroller discussion list - Public.
>> Subject: Re: [OT] Saving the world by consuming more fuel?
>>=20
>> I am curious here: where would all the extra energy be going? is the
>> backpressure causing incomplete burning and fuel is being lost without
>> all the energy being extracted from it, or is the engine becoming much
>> less efficient and all the extra energy is going into heat somewhere?
>> If it is the latter, it seems likely that something would have
>> overheated. I suppose that maybe the cooling system could handle it
>> but it certainly would be a big increase in waste heat.
>
>Pumping losses.  Energy is lost simply by having higher pressures in=20
>the cylinder during the exhaust stroke caused by exhaust restriction. =20
>The early catalytic converters on petrol(gas) engines caused a similar=20
>drop in economy and performance, though modern designs are much better.

I think instead it's because not all exhaust gases will escape, so less
fresh charge will be able to enter in the following intake phase.
Volumetric efficiency, in other words.

--=20
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