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BTU content of the various fuel blends

Is there a place that lists the BTU content of the various fuel blends used around the country in the summer and winter? For instance in the Kansas City area the EPA requires a special summer blend. Since I work in that area but live outside of it, I would like to know if it is better to go with the non-EPA blend. I am more interested in BTU’s as Octane levels don’t necessarily translate into better MPG’s. I am experimenting now, but it requires a slight detour to get the non-EPA blend and I am not sure I am saving anything.

Octane does not relate to BTUs; it just a measure of resistance to knock. High octane gas has no more heat content than regular; that’s why it’s a waste of money if your car does not need it.

The difference in summer and winter blends is mostly in the volatility; this is important for cars with carburetors to make them start easier; less important for cars with fuel injection.

I would forget about summer or winter blends and just tank what’s available; your DRIVING STYLE will determine mostly what mileage you get.

Heavy fuels, like diesel, have a higher heat content per gallon. But only a deisel can get this energy out.

Doc’s right. The only thing you might benefit from is ethanol content. Ask your stations whether they’re using E10. If you’re lucky, one might not be, and that should give you a slight (about 3%) mpg boost.

ethanol … E10. … should give you a slight (about 3%) mpg boost.

Why? As I understand it E10 has a lower energy content. It should give reduced mileage. I seem to recall a lot of people complaining about it. (I run diesel, so I don’t do ethanol, we just get the lower energy winter blends to reduce our winter mileage.)

I guess I stated it poorly - if you can avoid E10, you’ll get about 3% higher mpgs. I can’t avoid it around here.

BTU’s per pound:

Gasoline, 19,000
Ethanol, 12,600
Methanol, 9,600
Nitromethane, only 5,000, that’s why dragsters burn so much of it, on the other hand, a gallon of nitro weighs over 9 pounds.

no you stated this fine to begin with- - -I understood and agree with you.

That’s what I see with my 89 Tracer 1.6l. A 1-2 mpg drop when using E-10. I try to avoid it but in Missouri it is mandated except for Premium. I sometimes fill up at a Caseys just outside of the EPA mandated anti smog blend zone to save a little. However the clerk doesn’t know what’s in their gas and it’s not marked on the pump. They sell Regular and Super Unleaded, sometimes for the same price.