As first stated in the post this was not a question of efficiency, but in terms of increased "power" i.e. better acceleration. I have enjoyed reading these well constructed responses thus far.

Is it safe to say at this point in time that perhaps E85 is producing more power at a lesser efficiency?

And maybe I do not need to get my butt dyno recalibrated afterall ?

 

Good one, Tumba (both the pun and the observation) - and, you may well be right, although since we don't use direct injection, the additional fuel (vaporized) is going to displace a similar volume of air and the resulting increase in compression may be minimal.

Now if you put a blower on the engine, you DO increase compression.

- Jack

 

No, I think your "butt dyno" may well be calibrated correctly. In just a cursury search for information, I'm reading that E85 has approximately 72-75% of the energy per gallon that real gas has. Now, if two engines run at stoich, the difference in quantity of fuel used burning E85 is approximately 33.6% higher per cylinder charge than you have using real gas. So, this means that the 28-25% drop in energy is more than made up by the increased fuel charge.

Of course, you were feeling the power during acceleration, where it is likely that neither engine would be operating at stoich, both would be rich. But, my guess is the "rich" difference would be nearly identical between the two charges.

I DO think you felt greater power. You're just going to have shorter range.

- Jack

 

Excellent response, thank you.

The range is surely less, it was neat to see the computer show the adjustments. As I mentioned earlier the display for miles till empty jumped from 401 to 355 in a mile or so then it leveled out. It would have sucked if I did not expect it to do that.

 

I think that may be very safe to say.

Jack, we are definitely on the same page. What would be REALLY nice is an engine with a variable compression ratio - if the compression were to increase with the higher octane fuel, you would REALLY notice better performance - and probably gain some fuel mileage back too.

 

http://www.nissan-global.com/EN/TECH...N/DETAILS/VCR/

 

Good read...

 

Yes, variable compression would be great, wouldn't it? Even just for, say moving from 87 octane to 91 octane.

I was listening (on the radio) to the researcher who directed the Human Genome Project a few days ago and he's just founded a new venture that is in partnership with Exxon-Mobile to determine if it is feasible to produce biofuels from algae. Some of the advantages he talked about were that the algae essentially produced the fuel on it's own, without any additional energy consuming input like refining, that it will grow anywhere, not just in prime farmland and that it seems to have the potential of producing 10 times the fuel per acre "farmed" as corn. He called corn ethanol a "disaster", which I've believed it to be for a long time.

He said we could expect results within 5-10 years, barring huge setbacks. I'm hopeful.

I've enjoyed this discussion gang. And again, Labnerd, thanks for correcting me on the "lead" thing. I don't like it when I make stupidly incorrect statements.

- Jack

 

There ya go, malex - turbo, variable compression, knock sensor - keep everything optimized. Run anything from farm gas to straight alcohol.

 

I put E85 in once in the ole truck. Kicked the Edge up to level 3 and felt like a champ going home. Seen the best MPG of the entire time I owned the truck. It was a 5.4 FFV motor.

 

THAT I find kinda hard to believe! If it's true, why aren't you running it all the time?

 

Whatever advantages could come from ethenol. I do not like the fact we would be depleating our farmland and ruining the soil to grow fuel.
I'm not green by any means, but the soil can only produce so much, then we have nothing to grow our food with. Our farmland will end up worse than the dust bowl, or the Sahara.

 

And while we can still develop ethanol from other bio materials, if it is not a truly sustainable resource in the sense it will never power our entire nation, we should be concentrating our efforts on other bio fuel producers including algae.

Save the corn for cows, chickens, and people!

 

They are producing ethanol in Brazil from sugar cane, and they have a big surplus. Why aren't we buying it? Tariffs!

 

Updates updates.....so what about now 2 years latter?