Methanol vs Ethanol

[QKsilverF1]

does methanol's ability to be absorbed into the skin lesson when it is mixed with water (such as with windshield washer fluid)?

[Frank]

yes.

[TRRBOJEEP]

Quote:

Originally Posted by BadAssPerformance The real question is why someone would run alcohol injection? Most of the time it is better to just run the proper amount and octane of gasoline.

I appologize right off the bat, QKsilverF1, for getting off topic, but.... Just what kind of octane rating does one need, with gasoline, to run 32-35 psi of boost, JT? 110+?
(this boost level is possible with pump gas 92/93 octane + alky )

[Ondonti]

The octane you need all depends on your motor, how volumetrically efficient it is, how good of quench you have, how good your fuel vaporation is, spark plug location......

[TRRBOJEEP]

'89 T2... for arguments sake.

[Ondonti]

Frank, you posted some info and Im not sure what you mean by meth being more readily vaporized. The heat of evaporation of Ethanol is like 420 and Methanol is like 470 degrees.


BTW, for people talking about actual octane ratings of meth and ethanol, you really cant pin anything down. For some reason chemists cant tell the difference between high octane gas and low octane gas, so the only way they can get proper mix's is to use specially designed octane testing motors like frank posted info about.


I really dont think Ethanol or Methanol batches get tested at all for octane capability. Maybe Methanol made for racers gets tested but I dont know. So, batch to batch you probably cant rely too much on a certain octain #.


Now, I dont think its a good idea to go straigh alky on a motor that runs a lot. If you are under boost all the time (im not talking about a motor like stephanes that makes just a few trips down the strip and has constant oil changes) then you are likely going to be getting a good amount of alky into the sump, crapping up your oil. For that to happen you already have to be washing your cylinders and not making your rings happy. I would think if you arent careful about alky injection its very easy to overspray and wet down the cylinders causing these bad things.

[Frank]

Actually the reason you can't get a reliable octane is because each batch varies due to treatments, additaves, and the fact that gasoline is not one compound at all. It can vary, etc. There are different brands and mixes to make a Octane Rating. You can achieve it with cheaper and more additives, or more expensive with less additivies.

Methanol has a boiling point of 65degC which is 149degF. Ethanol is 78degC which is 172degF. I dont where you found your information. Boiling point is the positive state change between liquid and vapor.

Methal and Ethal Alcohol are a constant octane. Anotherwards they typically dont very at all. They have a fixed octane, and it assumed. Its no different then racers, other then it will carry an octane rating because its for use with cars.


Frank

[Ondonti]

I was quoting latent heat of evaporation from a fuel chart I have.

Even pure gasoline has different octanes.

They lost a lot of Fighter plane motors in WWI and they had no idea why till they figured out the octane thing....and the only solution was to test gas beforehand in those special machines to figure out what each batch was exactly.

They cant just pump out a certain octane Gasoline regardless of additives. Ill assume the addivitives have a known octane as well as alky. Pure Gasoline isnt like that for some reason. They have to test before they start mixing things in. Often its cheaper to just change the amount of additives to get the proper RON/MON then try to get the perfect batch of gasoline.

There is no apparent chemical difference between a high octane batch of gasoline and low octane batch. Im not talking about prepared fuels at the pump.

I have wondered if its better to use the USA method of octane rating over the european RON # since RON doesnt really say anything about what the MON will be. You can have 98 ron of 85 MON, and 98 RON of 81 MON. HUGE difference.

[B.A.P.]

Quote:

Originally Posted by TRRBOJEEP I appologize right off the bat, QKsilverF1, for getting off topic, but.... Just what kind of octane rating does one need, with gasoline, to run 32-35 psi of boost, JT? 110+? (this boost level is possible with pump gas 92/93 octane + alky )

Well, its not just octane, it depends on both octane and how much fuel ya got.

I've never personally run more than 30psi, but on my stock T2 shadow I've run 27psi on 100 octane thru 42pph injectors at close to stock fuel pressure. And on my Z with a big hybrid turbo ran 30 psi on 100 octane thru 72 pph injectors running 80% duty cycle at 11:1 A/F also at close to stock fuel pressure.

[Frank]

Hmmmm. Lets try a better approach.

You start out with crude oil. When you refine it, you can get

Paraffins - methane, ethane, propane, butane, isobutane, pentane, hexane
Aromatics - benzene, napthalene
Napthenes/Cycloalkanes - cyclohexane, methyl cyclopentane
Alkenes and Dienes - ethylene, butene, isobutene
Alkynes - acetylene, butadienes

When you refine crude oil, you get all of those compounds. This is done by heating the crude oil to vapor. Depending on the molecular weight, some will rise higher then others. This list above is in proper order from lightest to heaviest. The weight is typically defined by the number of carbons in the chain with respect to how many hydrogen atoms. In its early stages, gasoline is C5 thru C12 since its not easy to get just more molecules in the upper range. You can then use different crackings, catalyists, and reformers to get you gasoline to a higher quality or reduce heavers into our standard "gasoline". However each batch varies. They are then tested and catagorized into a certain octane of gas based on their concentrations of the various carbon chains. There are treatments to adjust it to the standard octanes, and their are also treatments to raise the MON higher. This is why it is vital to run heavy boosted cars on high MON pump gas, however MON is the extreme end of realizm for most cars.


Frank

[TRRBOJEEP]

Quote:

Originally Posted by BadAssPerformance on my stock T2 shadow I've run 27psi on 100 octane thru 42pph injectors at close to stock fuel pressure. And on my Z with a big hybrid turbo ran 30 psi on 100 octane thru 72 pph injectors running 80% duty cycle at 11:1 A/F also at close to stock fuel pressure.

I wasn't aware you could get that much on 100 octane.

Quote:

Originally Posted by Frank You start out with crude oil. When you refine it, you can get Paraffins - methane, ethane, propane, butane, isobutane, pentane, hexane Aromatics - benzene, napthalene Napthenes/Cycloalkanes - cyclohexane, methyl cyclopentane Alkenes and Dienes - ethylene, butene, isobutene Alkynes - acetylene, butadienes

Frank... you're the smartest white boy I know! lol
Where do you come up with all this knowledge?

[Frank]

<--- D in chemistry, but A in researching! Actually I got the information from 6 different websites, my internal combustion engine book, and my chemist friend.

There is way, way, way more information, however I didnt want to go there. Its nuts the whole refinery process!

Quote:

Originally Posted by TRRBOJEEP I wasn't aware you could get that much on 100 octane. Frank... you're the smartest white boy I know! lol Where do you come up with all this knowledge?

[Putter]

Ya, no kidding, you barely explained a cracking tower...

[ash]

Quote:

Originally Posted by QKsilverF1 I posted this over at srtforums as well here is the link if you want to read what other people think http://www.srtforums.com/forums/showthread.php?t=204379 ok ive been doing some research on the internet and what do you know, the internet sucks at giving consistent info. here goes this site says a 50.50 water ethanol mix is best and the Meth is not good. i quote " 4. Methanol, as an additive, is not a practical choice as it is prone to pre-ignition, is not safe to handle and is not readily available." http://www.rbracing-rsr.com/waterinjection.html I dont see how the "prone to pre-ignition (knock)" can be true due to its high octane rating and that ALOT of people use it to reduce knock Including those people in the indy 500 who run straight meth for fuel. Other sites say methanol is the best, one even says straight meth is not corrosive to your fuel system or rubber..... "Methanol has no effect on rubber, neoprene or OEM carburetor or fuel system parts nor does it get stale like gas does. But it will corrode aluminum as plain water does if it is not drained and allowed to evaporate from the fuel system over an extended length of time." http://sneakypetespullers.com/technical%20Articles.htm Why do so many people talk about how corrosive to the fuel system it is? Wikipedia gives these octane ratings for the fuels Methanol 123 Ethanol 129 from (scroll half way down to the table) http://en.wikipedia.org/wiki/Gasoline This site says Methanol 99 Ethanol 100 http://www.leeric.lsu.edu/bgbb/7/ecep/auto/m/m.htm This site says Ethanol 113 http://www.gov.mb.ca/est/energy/ethanol/ethanolfaq.html http://www.srtforums.com/forums/showthread.php?t=107888 FastAttack says "Alky , is a type of alchohol used primarly to decrease the temperatures of the charged air , although cheaper than methanol , it will vaporize a lot faster than methanol or water thus not having the same level of efficiency in cleaning your motor and preventing detonation." Doent all fuel vaporize by the time it is ignited anyway??? im pretty sure enough heat is produced during the compression stroke to vaporize all the fuel "gas/meth/eth/water" etc. in the cylinder also if eth has a higher octane rating than meth wouldnt it be better at preventing knock? Here is an MIT PDF about Direct Ethanol Injection http://lfee.mit.edu/public/LFEE_2005-001_RP.pdf Other sites with info if you are interested http://www.energy.ca.gov/afvs/vehic...s/methanol.html http://www.agriculture.state.ia.us/e85q&a.html http://www.palatineoil.com/fuels.html http://www.ncga.com/ethanol/main/your_car.htm So can someone who actually knows please clear up my confusion. please tell me what the differences between ethanol and methanol are (as well as advantages/disadvantages to each) and try to clear up some of the contradictions found in my links. Again please only post if you actually know what you are talking about and can back it up with an understandable explaination Thanks

OK...
The quick answer first.
Methanol is great for decreasing intake air charge. It also adds torque to your engine. Ive never heard of methanol having pre-ignition problems... contry to that actually.
Methanol is corrosive! .Need to clean out your system , and can cause failure to parts if it is not cleaned.
About the same power obtained through ethanol, as to methanol. WE had a blown car that was converted to ethanol , ( live in a sugar cane growing area here.) to show the "good" points for green house gas problems....
Methanol should be heaps cheaper too. Over here we pay about $200 au for 205 liters or 44 gal
Hope this helps
Ash

[Ondonti]

Im still not certain about this testing of gasolines octane. I took an organic class and we learned about the crude distilations so I understand that process.

What I dont understand is why they have octane testing machines rather then chemically figuring out what the octane of fuel is. Simply following the "rules" of increasing or decreasing Supposed MON ratings with additives on the octane testing motor is not going to mean that 2 fuels with the same MON will act anything like each other or even have the same detonation characteristics in real life usage.

If fuel mixing is such an art, why are these same chemists unable to even tell what in the world the fuel is chemically without mechanically testing it. I really dont understand this.