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Since we are on the topic of fuels....It has been suggested to me that a 50/50 mix of water and methanol injected into the engine (wide open throttle) would help greatly to avoid detonation (higher octane and lower intake temps) while using pump gas. If I understand this correctly the 50/50 mix on its own does not make power but lower intake and cyl temps allow for more timing and leaner AFR which does make power.

I wanted to know if this would help the losses of power from 110 deg temps in havasu AND if injecting prior to the throttle body in a 525EFI would allow the engine to adjust on its own without a recalibration to the ECU (since the injection would cool the intake charge). I posted this already but have not had a response. Thank you.
 

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I'm just going to throw this out there, please don't take offense.;)

The energy content of a fuel has little to do with how much horsepower it can produce, in fact quite the opposite.

For an example, octane rating (how controllable a substance burns) has way more to do with it than anything else....

Gasoline has a BTU content of approx. 18,500 BTU/lb., whereas Methanol has approx. 9500 BTU/lb and can make quite a it more power, just need more fuel, now Nitromethane contains approx 5000 BTU/lb...

So I guess to answer your question, you will be at approx. 18,500 BTU/lb with race fuel, that number really does not go "up" as the grade of fuel is increased, but rather "down"....

Does that even come close to answering your question...:)Unsure

Makes little sense if the basics aren't followed, knowhatamean?;)

GT :)hand
ive heard from many different people that a lower octane rating (87) is better for higher elevations... is this true?
 

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ive heard from many different people that a lower octane rating (87) is better for higher elevations... is this true?
It is true that at higher elevations (say 5000') there is less air and hence your effective compression ratio goes down, and so you can get away with a point or two less octane for a given motor.
 

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ive heard from many different people that a lower octane rating (87) is better for higher elevations... is this true?
Sorta...

You can jet down and bump the timing at altitdue, if you are adjusting for higher elevations, I would say no, but if you want to "run what you brung" at 3500-5000', then that would be true.

If you do some ragged edge adjustments then I say the higher the better as far as octane.

GT :)hand
 

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There are two things wrong with this page:
The first is that you misspelled the word "Which" in the headline. You spelled it as "wich." And you left it like this for a decade and a half.
The second is that BTUs are irrelevant when discussing fuels for internal combustion engines. Read my two reports on this issue at:

The Irrelevance Of BTU Rating - Big Oil's Gimmick To Hoodwink The Public
The Irrelevance Of BTU Rating - Big Oil's Gimmick To Hoodwink The Public

The Irrelevance Of BTU Rating - Revisited
The Irrelevance Of BTU Rating - Revisited
 
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