E85

[RichP]

Kinda like the early difference between IBM PC's and Apple computers - going to the "open" architecture allowed IBM to give Apple a thorough clobbering in the market - and they're still recovering (note that the PowerPC/PowerMac finally adopted the PCI bus, and they've probably finally caught on with AGP as well. I also find it telling that Apple offered Intel's USB before their own FireWire/IEEE-1384...)
5-90

Partly true, both apple and ibm went propriatary bus, ibm went micro-channel and when the powerpc came out in ahhhh, ~96/97 it was sold under both the IBM and apple labels and ran AIX/CDE, even now you can install AIX on the apple branded ones and you can run the apple OS on the IBM ones. IBM's microchannel architecture was licensed, if you wanted to build cards you had to pay IBM a fee and they would give you a block of numbers the chipset on the board would recognize which meant you had to pay for how many cards you wanted up front, very unpopular for the video and modem companies, one reason external modems hung around in corporations for so long, IBM could not really lock down the serial ports. A compay in SanDiego Calif, Regal, built IBM microchannel clones, to even replace a HD you had to buy it from either IBM or Regal, they had a string in the HD firmware that the system needed to even see the drive and the drives cost 2x the normal price, 500meg Conner drive was $600 vs the same drive at compusa for $250. Hence The 'Gang of 7', Gateway, Dell, Packardbell, etc got together and devleoped/accepted a standard ISA, VESA, EISA and later adopted PCI standard they all decided to build to, ticked IBM off no end. Even to this day IBM uses Micro-channel though in a limited number of systems.

 

[krakhedd]

Vesa local bus....wow....I still have a 486 and a 386 sitting around that utilize this bus, and also, have some expansion cards. I remember trying to build a computer in my early or mid teens, and I couldn't find any parts because PCI had been introduced by then. Maybe I was looking for parts in all the wrong places?

 

[WB9YZU]

It would make sense, but I haven't checked AvGas additives lately. Still, considering temperature drops at altitude, it would be a good idea.
Part of the reason for such high octane in AvGas is that the engines are designed with high sea-level compression, so it can make up for paucity of air at altitude. 5-90

No, and no.
100LL AVgas does not have an antifreeze additive.
AV engines do not have higher CRs to offset the affects of thin air, most don't even have high CRs. Your example of forced induction is not related to CR, except to say that it is usually an inverse ration. The more forced induction, the smaller the CR.

Back to Ethenol.
Alcohol has 1/2 the avaiable BTUs as Gasoline per volume. That means you will need twice the amount of alcohol to get the same amount of energy as Gasoline.
As another poster mentioned, this really causes a large decrease in gas milage.
In order to run E85, your PCM will need to deliver around 85% more fuel it currently delivers to the engine.

A discussion about octane occured some where around here.
This too is simple and has less to do with big words than comon sense.

The Octane number is the compression required to self ignite a fuel.
(used to be done with an adjustable compression engine)
The lower the number, the lower that compression is. You must match the fuel with the engine.
If you try a low octane fuel with a high compression engine, it will ignite too quickly and the engine will not be able to harness the maximum available energy.
If you try a high octane fuel in a low compression engine, it will ignite to slowly and again, the engine will not be able to harness the maximum avaialble energy.

Alcohol, as a poster mentioned, has a very high octane ratio.
To get the most out of E85, one would have to bump the CR up on a engine.

I found tis article worth reading about E85 conversion
http://www.engr.unl.edu/~ethanol/unl-sae2.pdf#search='E85%20engines'

You may also want to look up old copies of Mother Earth News circa mid 70's as they did a few full conversions to homebrew alcohol with carburated engines.

Ron

 

[WB9YZU]

Some interesting facts about alcohol that I was mistaken about.
The BTU factors for alcohol differ by type of alcohol.
Gasoline is 150K BTU/Gal
Ethanol is 101K BTU/Gal
Methanol is 75.4K BTU/Gal

So actually Ethanol has 67% the energy of Gasoline, not the 50% I assumed for all alcohol (based on Methanol data).
That would mean that the 85% figure I stated for extra fuel flow would be BS
For E85, something in the order of 30-40% additional fuel flow seems like it would be more realistic.

Ron

 

[Beej]

Isn't this thread from last August?

 

[WB9YZU]

Likely
Still, it's an interesting subject.

 

[krakhedd]

Interesting like examining one's own feces after a trip to the office?

The only good thing about alcohol for domestic (read: non-racing) engines is the fact we're not relying on oil from other countries (f*** the politics involved - I don't like supporting our economy by importing anything from any country), and the fact that we're already paying farmers not to farm some of their land. If those same farmers were to use that same land to grow corn, and then converted that to ethanol, and we could all run pure ethanol, then guess what? Renewable resource, with no need whatsoever for importing products. But there's too much money to be made importing and selling fossil-based fuels, so that won't happen, at least not anytime soon.

Also, we could grow soy on those same fallow lands, and convert it into vegetable oil, then biodiesel, and further reduce our dependency on foreign oil. We could use the biodiesel to heat homes that use heating oil; we could use it as jet gas; and we could use it as a kerosene substitute. Again, too much money tied up in importing from the rest of the world and distributing domestically........