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ALCOHOL/GAS MIX?

Posted: Wed Nov 19, 2008 8:03 am
by BEDNAR1320
HAS ANYBODY TRIED A 50/50 OR ANY OTHER RATIO ALCOHOL/RACE GAS MIX. SEEMS LIKE YOU WOULD GET THE BEST OF BOTH WORLDS WITH A MIX LIKE THIS,OR IS THERE SOMETHING THAT WOULD KEEP THIS FROM WORKING WELL :?:

Posted: Wed Nov 19, 2008 8:27 am
by Dave Koehler
Methanol and gas do not mix. Ethanol and gas do.

Posted: Wed Nov 19, 2008 9:11 am
by BEDNAR1320
I GUESS IT IS AS THEY SAY "MY BAD" :oops:

Posted: Wed Nov 19, 2008 6:01 pm
by Tuner
This thread explains one of the big problems with mixing leaded race fuel and alcohols

http://www.innovatemotorsports.com/foru ... hlight=MMT

This particular post gets to the point.

http://www.innovatemotorsports.com/foru ... stcount=22

Metallic octane improvers (TEL, TML and MMT) have a negative effect in alcohols. They lower the octane and increase the pre-ignition sensitivity.

Posted: Thu Nov 20, 2008 8:29 pm
by Greezer
HAS ANYBODY TRIED A 50/50 OR ANY OTHER RATIO ALCOHOL/RACE GAS MIX
Like E85?

Posted: Tue Dec 02, 2008 11:48 pm
by David Redszus
Metallic octane improvers (TEL, TML and MMT) have a negative effect in alcohols. They lower the octane and increase the pre-ignition sensitivity.
Actually, organometallics such as TEL and TML, have absolutely NO effect on the octane rating of methanol. That is based on the addition of TEL/TML being added "neat", that is not mixed with a gasoline base.

The determination of octane ratings with methanol is problematic and published octane ratings are often in error. Methanol does not respond as does gasoline when tested on a Waukesha Octane Test engine.

When methanol and gasoline are mixed, a hydrogen bonding reaction occurs which will raise the vapor pressure of the fuel. Now it is difficult to obtain an accurate measurement of RVP.

When alcohols are used, they are typically used in small concentrations (10-15%) being added to gasoline, not the other way around. Higher concentrations cause all sorts of other problems.

Posted: Fri Dec 05, 2008 10:14 pm
by Tuner
Actually, TEL absolutely DOES have a negative effect on methanol and ethanol. TEL increases methanol’s pre-ignition sensitivity, which is already poor compared to gasoline. Refer to SAE paper 821210 “Pre-ignition and Knock Behavior of Alcohol Fuels”, by Volkswagen Research. A Bosch paper I can’t find to cite at the moment also reports unfavorable effect with TEL in methanol. Pre-ignition, of course, is a precursor to knock.

In Edward F. Obert’s “Internal Combustion Engines”, third edition, Ch.8, Table 8-7, pp.240-241, 3ml TEL/gal in ethanol LOWERS octane from 107 to 102 (Research). Granted, that’s with the CRC engine and procedure which, as you said, is problematic with alcohols but it is in consensus with several other similarly credible sources.

I know from experience that engines run on methanol with MMT added can have catastrophic preignition with the ensuing detonation and engine failure. If you have the means to test this on your own engine, do so. This is in the context of engines optimized for methanol, like a 410 WoO sprinter or an 18° 434 15/1, etc, no rookie junk.

You can call it a matter of semantics or spin it anyway you like, but I think it’s irresponsible to tell people “organometallics such as TEL and TML, have absolutely NO effect on the octane rating of methanol” when the addition of TEL to alcohols is cited in several reputable sources as causing preignition and abnormal combustion.

Gentlemen, if you mix alcohols and race gasoline, don’t use leaded gasoline. Don’t add MMT octane booster to alcohols or a blend of alcohols and gasoline. Some unleaded pump premium contains MMT. It’s what makes the tan or brick reddish colored deposits on the sparkplug ceramic. Some unleaded race fuel may contain MMT because it isn't lead and it is effective in raising octane number so check the manufacturer’s MSDS or call them and ask if you intend to blend with alcohols.

Posted: Sat Dec 06, 2008 1:09 am
by David Redszus
but I think it’s irresponsible to tell people “organometallics such as TEL and TML, have absolutely NO effect on the octane rating of methanol” when the addition of TEL to alcohols is cited in several reputable sources as causing preignition and abnormal combustion.
Well I strongly beg to differ.
The use of alcohols blended with all sorts of other compounds (including leaded aviation gasoline) was throughly investigated before and during WWII. Several NACA papers have been written on the subject.

During th 1930s and 1950s various racing engines used blends of methanol and leaded aviation gasoline. These included the Offy engine, CooperCoventryClimaxIndy, AutoUnion, MercedesBenz, Alfa Romeo, and the 1930 Fiat Aero record plane.

Quoting from one technical paper:
"The alcohols, not only do not detonate but also have virtually zero lead response, hence lead doping of alcohol blends with TEL and TML appears to be futile."
Racing experiences with Methanol and Ethanol based Motor Fuel Blends, SAE 750124, T. Powell

We are currently involved in a factory racing project that uses alcohol with leaded race fuel. It has also been used as a cheater fuel in go-kart racing for many years.

Some of the apparent confusion may be the result of the fact that alcohol fuels do not detonate. Therefore the octane level cannot be effectively measured and loose estimates are often used. The addition of lead will produce no change. But the addition of gasoline, leaded or unleaded, may indeed alter the detonation characteristics of the fuel blend. But that is due to the gasoline, not the lead. There are several race fuel blends, currently on the market that contain both alcohols and lead compounds.

Just because alcohol fuel does not produce detonation, that does not mean that it cannot produce pre-ignition, excessive combustion temperatures and find other unique ways to destroy an engine. Pre-ignition is not always a precursor to detonation but it certainly is a precursor to severe engine problems.

Posted: Sat Dec 06, 2008 5:40 pm
by Tuner
David Redszus Posted: Fri Dec 05, 2008 11:08 pm

Well I strongly beg to differ.
The use of alcohols blended with all sorts of other compounds (including leaded aviation gasoline) was throughly investigated before and during WWII. Several NACA papers have been written on the subject.

During th 1930s and 1950s various racing engines used blends of methanol and leaded aviation gasoline. These included the Offy engine, CooperCoventryClimaxIndy, AutoUnion, MercedesBenz, Alfa Romeo, and the 1930 Fiat Aero record plane.
What’s your point? My motive is to avoid the spread of misinformation and reduce the collateral damage of engines belonging to people I will never have the pleasure to meet.

In the “1930s and 1950s” drivers wore leather helmets and fire retardant clothing was cotton coveralls soaked in a Borax solution. The Avgas used in much of the NACA research was 115-145, anybody smart would have used it for racing and we should be so lucky. I haven’t had the pleasure since 1974. As time passes we humans learn, gracefully if we’re lucky, hopefully not from our own mistakes or the unfortunate mistakes of others. You state your opinion as if anyone with information contrary to that which you choose to believe is misinformed. It’s possible you’re not the only person to have read NACA papers or used methanol and Avgas, maybe several others have too, they might even be reading this. It’s possible someone who did some of the research will read this. Imagine that.
Quoting from one technical paper:
"The alcohols, not only do not detonate but also have virtually zero lead response, hence lead doping of alcohol blends with TEL and TML appears to be futile."
Racing experiences with Methanol and Ethanol based Motor Fuel Blends, SAE 750124, T. Powell
The futility is in referencing that quote. Alcohols do knock and they do respond to lead, however in a negative manner. Mr. Powell’s remark “virtually zero lead response” is in the context of the lead didn’t raise the octane. More recent research employing scientific method shows lead to cause a negative effect, at least in the test cases referred to in the Volkswagen paper and others. Several papers discuss knocking behavior of alcohol fuels. SAE 880174 describes methanol’s octane behavior as 71 and 57 in the tested conditions in a two-stroke engine.

The VW paper’s emphasis was on methanol’s greater self-ignition sensitivity than other fuels and in that context describes the effect of TEL on methanol’s knock behavior with the word “negligible”. Graphic data in the paper clearly shows a negative knock effect but it’s rendered a moot point because the TEL lowers the threshold for self-ignition such that the pre-ignition limit is met before the onset of knock.

We all know of, and the papers refer to, methanol’s high octane behavior with rich mixtures. In reality, where things can go awry and combustion conditions can be undesirable as described in the papers, every little thing is important. The leather helmet is OK until you’re sliding along on your head. The negative effect of a metallic, however minimal, is no more acceptable than “just a little bit too lean”.

If it’s your own engines involved in the testing you’re doing, believe what you will, but if you have a fiduciary responsibility to the factory you’re involved with on the racing project I suggest it would behoove you to look further into this.

Re: ALCOHOL/GAS MIX?

Posted: Sun Dec 07, 2008 11:43 am
by Doug Schriefer
BEDNAR1320 wrote:HAS ANYBODY TRIED A 50/50 OR ANY OTHER RATIO ALCOHOL/RACE GAS MIX. SEEMS LIKE YOU WOULD GET THE BEST OF BOTH WORLDS WITH A MIX LIKE THIS,OR IS THERE SOMETHING THAT WOULD KEEP THIS FROM WORKING WELL :?:
Has been done many times, but the bottom line is they won't stay mixed. Picture a bottle of Oil and Vinegar. For what it takes to do, and what the results are you're better off going to a different combination, or running an Ethanol blended fuel.

Posted: Sun Dec 07, 2008 11:46 am
by Doug Schriefer
Greezer wrote:
HAS ANYBODY TRIED A 50/50 OR ANY OTHER RATIO ALCOHOL/RACE GAS MIX
Like E85?
E85 is Ethanol and Gasoline. Ethanol and Methanol are different.


Now while Tuner & David are both correct. The bottom line is that there are much better alternatives than trying to mix methanol and racing gas so why waste your time

Posted: Sun Dec 07, 2008 1:38 pm
by Tuner
word

Posted: Sun Dec 07, 2008 2:37 pm
by ProPower engines
I have first hand info that back in the early indy days they did mix methanol and gas a method of getting more power and cooling.
A local fellow and widely respected indy car builder from my area named
Grant King and I had many talks regarding fuel mixtures for old style modifieds ect and went in to detail on mix ratios for carbed and injected engines and results relating to what altitude ect but methanol and gas do not stay mixed but,
they used aceitone as a binder to keep it mixed and prevent it from seperating.
Although this is real old racer go fast stuff and I know that some info published says it won't work but never under estimate a racers determiation to find a way to go faster or make more power.
I have used his info regarding this in carbed applications and it works
Maybe a fluke I don't know but the results were impressive.

Posted: Sun Dec 07, 2008 2:50 pm
by PWMAX
I think it may be Chuck Nyuten, but I did see an add in the Dragster, a while back, from a big carb shop, selling 50-50 gas/alky dominator carbs, and the add explained all the benefits. More consistent, less change in et from weather changes, and the big one, less moisture, and oil contamination and corrosion, associated with methanol

Frank

Posted: Sun Dec 07, 2008 3:46 pm
by Greezer
Quote:
HAS ANYBODY TRIED A 50/50 OR ANY OTHER RATIO ALCOHOL/RACE GAS MIX

Like E85?
E85 is Ethanol and Gasoline. Ethanol and Methanol are different.


Now while Tuner & David are both correct. The bottom line is that there are much better alternatives than trying to mix methanol and racing gas so why waste your time
I only injected that because, as you state here, 'why waste your time?' E85 is what it is, there are engines running it at 9:1 on up to 14:1 and some claim higher. No need to mix anything. I'm about to try the E85 on a 383 or 400 based mill as soon as I figure out exactly what I want. This for my own personal use, carbed.