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Poor MPG

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At a basic level an engine is an air pump. Smokey Yunick was an expert at this theory. The more air an engine can move the more efficient and effective it is. Thus cool, dense air is better for engines than warm, thin air. Remember the move to intercoolers when turbos were all the rage a few years back? Now it is summer and the air is warm and less dense, it takes MORE air to achieve the same efficiency as cooler air. Now the engine has to work X percentage harder which means MORE fuel, not less to achieve the same results.

As always, if I am mispoken, please feel free to jump in.

And how about this Catch-22: Gas prices are soaring so it now costs more to get goods - food - to market which means the cost of goods is going up and we need more money for gas AND goods and because the ethanol blend fuels burn less efficiently we have to use more gas which drives the price of the goods even higher which means we have to spend more money on gas and have less for goods which we are burning up in the fuel which we are using to get the goods to market (and then there is the piece that the corn that goes into ethanol is not the same grade that is sold for human consumption?) and so on and so on..... Oh my brain hurts!!
 
I see your point silverghost, and I think you are partly correct. I think that the extra gas needed for power in warm temps is offset by warmup in cold weather and cool air requiring more fuel to maintain stoichiometric ratio in the cold weather.

As you said, the engine is an air pump. If I am rolling down the freeway at 2500 rpm's in 30* weather and in 90* weather, the engine is consuming the same volume of air. The difference is that the cool air is denser and contains more oxygen, requiring more gas to maintain a proper ratio and not go lean. Makes sense (and you can feel it) that the vehicle has less power in warm humid air, however, I think that the economy loss from that is far offset by the cruising. At least, in my case, this seems to always be true.

In short, cool air is like a mini-forced induction system as it gets more oxygen into the engine.
 
Ugh! According to my brief research it is the other way around. Summer gas formula, on average, delivers better gas mileage. It's the winter gas that has all the ethanol. It's an anti-freeze for the gas.

Back to the drawing board.
 
Always Zimmy. Just love a cool nite at the track.
 
So maybe the thread on cold air intake that I tacked onto earlier today is a good idea? Hmmmmm
 
Update:

I remapped my ignition (I retarded things a bit) and beat 30mpg on my last tank (which was mostly city driving!).

If I can get over 30 for the next few tanks, I will be happy.
 
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