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While reading a Belgian consumer magazine, I just found out today that my usual gas station here in Belgium has one the worst fuel quality.

(Makro, a subsidiary of the German Metro group)
The problem, which affects many gas stations in Europe, is an octane booster additive called MMT (methylcyclopentadienyl manganese tricarbonyl ).
Very high concentrations were found in 95RON fuel in many brands of gasoline across Belgium. Some brands however had no traces of this harmful additive (Shell , Esso, Texaco)
This additive has a negative impact on sparkplugs longevity, catalytic converter, exhaust systems, O2 sensors and can affect your gas mileage, performance as well as how smoothly your engine runs.
I’ve experienced very short sparkplug life on my LPT (Makro 98RON )and the engine runs less smoothly than my sister’s LPT (Shell 95RON)
Apparently, there are no legislation against the use of this additive in Europe and the additive is used in many European and foreign countries whereas the US has a maximum legal concentration allowed of 8.26 mg/L or 0 mg/L in polluted area.
The concentration found here were as high as 27 mg/L in 95RON fuel, and higher concentrations are likely on 98RON fuel according to experts (98RON fuel not surveyed)

I did a quick search on the net and found this interestingf article which highlights the issues


Form canadiandriver:.com


March 10, 2004
MMT: the controversy over this fuel additive continues
by Jim Kerr

MMT, Methylcyclopentadienyl Manganese Tricarbonyl, has been a controversial fuel additive for many years. In Canada, most of our fuel includes MMT as an octane enhancer to help prevent engine pinging or knock. In the United States, MMT has been banned in the past but is now allowed in some parts of the country. Even though it is allowed, MMT is still not in common use in the U.S.
Ethyl Corporation, the sole manufacturer of MMT claims that MMT is beneficial to reducing vehicle emissions. While MMT is an octane enhancer and may provide some advantages studies by the automotive industry would indicate otherwise.
Over 30 papers have been published by the Society of Automotive Engineers (SAE) on MMT fuel additives. Many of these have indicated MMT increased tailpipe emissions, spark plug fouling, catalyst damage and impairment of On Board Diagnostic systems. While it is claimed these studies were not of enough depth to indicate accurate results, the latest study released in 2002 has the statistical controls and research methods to accurately determine the effects on MMT additive on vehicle emissions.
Conducted jointly by the Alliance of Automobile Manufacturers, the Association of International Automobile Manufacturers and the Canadian Vehicle Manufacturers' Association, this eight million dollar study is the most comprehensive study on the effects of MMT on vehicle emissions to date.
The test used 56 vehicles from 6 major automotive manufacturers. Side by side testing was performed on two pairs of matched vehicles, with half of the vehicles using fuel with MMT additive and the others without MMT. Emission levels were tested several times during the evaluation program, during which the vehicles accumulated up to 160,000 kilometres. A total of 5,840,000 kilometres were driven during the six year test.
Between 4000 and 50,000 miles, MMT fuelled vehicles had hydrocarbon emissions averaging 13% higher than non-MMT fuelled vehicles. CO was about 6% higher but NOx was reduced by 10%. Spark plugs in two of the test vehicles fuelled with MMT misfired to the point of turning on the Malfunction Indicator Light (MIL). Evaluation of the plugs by Delphi, the plug manufacturer, found that reddish brown deposits were on the tips of the plugs exposed to MMT. Delphi theorised that the manganese oxide deposits on the plugs are conductive under high heat, causing the plugs to track down the insulator and misfire. Several other vehicles also experienced sparkplug misfires but not severe enough to turn on the MIL.
Fuel economy tests were also performed during the study. City fuel economy for vehicles using fuel with MMT were consistently lower than for vehicles not using MMT. The difference at 15,000 miles was .35 mpg U.S. and increased to .48 mpg U.S at 35,000 miles. Highway fuel economy was lowered by .2 mpg U.S. This is a significant reduction in economy over the life of an automobile.
Who does one believe? Ethyl Corporation claims MMT is beneficial and they have the research to back up their claims. The auto industry research shows MMT causes vehicle problems, higher emissions and lower fuel economy. Both have a lot to loose. If MMT continues to be added to fuel, the auto manufacturers will have to spend huge amounts of money to design emission systems compatible with MMT. If MMT is banned, the refining of fuel could be more costly or other octane enhancers will be required and Ethyl Corporation would not be able to sell MMT.
The Canadian Government did try to ban MMT. In 1996, Environment Canada announced that it would control MMT under a trade bill, Bill C-29 (the Manganese-based Fuel Additive Act), claiming that MMT can impair the on-board diagnostics and air pollution control devices of vehicles and thus indirectly harm the health of Canadians. In 1997 this bill came into effect, banning importation and inter-provincial movement of MMT. However, in 1998, Bill C-29 was rescinded after a panel formed under the Agreement on Internal Trade found that this bill was inconsistent with the government's obligations under the Agreement on International Trade. Ethyl Corporation had also challenged Bill C-29 and the government's right to restrict trade.
In an out of court settlement with Environment Canada, Ethyl Corporation received a $13 million settlement for "reasonable cost and profit" lost because of the implementation of C-29.
Is MMT all right or is this really political posturing to support economic trade? I tend to believe the validity of the automotive industry's study.
Finally, studies by Health and Welfare Canada (now Health Canada), on the health effects of MMT in fuel found no significant health effects associated with exposure to manganese exhaust emissions. Meanwhile, other Canadian researchers and the U.S. environmental Protection Agency disagree with Health Canada. It would appear that more scientifically based research is needed to find the real truth on the health effects of using MMT in fuel. The controversy continues.
 

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For what it's worth MMT has just recently been completely banned from use in all of California. Instead use of Ethanol to increase octane has now been implimented.

Sadly using ethanol is not an effective means for compensating the octane decrease. The AON (Average Octane Number) remains 91 octane here in Cali, however because ethanol is more sensitive to temperature, the MON (Minimum Octane Number) has actually gone down. In Europe it may been even worse as you use RON (Research Octane Number) which does not even take into account the MON. (AON is an average of the two.)

This means that the fuel's tendancy to knock increases even more than it used to when heated. Sadly turbo engines are most effected by this.

I would have liked to see Toluene used for octane additives. It's more expensive than Ethanol, but has a higher RON and MON. Unfortunately it's harmful to the environment in un-burnt form, so any leaks from fuel tanks would harm the environment. (Once burnt it's harmless, as it is a pure hydrocarbon.)

Anyhow ... MMT shouldn't have ever been used in the first place. It's not a very effective octane additive, it's potentially harmfull in both un-burnt and burnt forms, and Toluene has been used as octane booster effectively since the late 70's. It should have been a better choice.

Dubbya~
 

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Originally posted by scminks:
[qb]i can buy toluene at £18 per 5 imp gallons.what ratio would be best??(cs carly)
simon [/qb][/b]
Generally you want to use no more than about 20-30% of the volume of your tank. So no more than 5 gallons out of 15.

It also depends on your octane rating. Toluene has an RON of 117. If your tank is 17 gallons and you mix 5 of toluene with 12 of 98 RON unleaded you'd get about 103.5 RON. This would be ideal for track days to ensure zero detonation.

For daily driving one gallon would give you 99 RON for about 3 extra pounds per tank. Two gallons would be 100 RON for about 7 pounds extra per tank.

However don't let the numbers fool you. Buying 100 RON will likely result in a lower MON and AON due to large concentrations of Ethanol. Mixing it with Toluene will make it more detonation resistant in those stricter conditions.

At any rate, in Europe it's possible (due to excessive fuel tax that does not apply to toluene) that it may be a practical solution to low octane. But here in the US unfortunately it is not, as our gas is about half the price and Toluene about the same.

Great idea for track days. Throw in 5 gallons and enjoy some extra
....

Dubbya~

edit: Toluene also provides more BTU's of heat per unit volume than Ethanol. Toluene is closer to gasoline and should keep your a/f ratio more consistant than Ethanol, not to mention giving you more power because of the more concentrated fuel.
 

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My car is a 1994 2.3T CSE, tuned up (theoretical to around 260BHP with remapped ecu, bigger back box, no cat, dump valve, bleed valve etc.

Only say all this to get onto the Toluene question. Being a non-technical bod, should I buy the stuff and put it in for road use, and if so what would be the upper safety/sensible percentage limit ??

Also, in laymans terms what will it do for me sitting behind the wheel ??

Finally, who sells it please ??
(Simon - you can get it for £18 per 5 gallons, do you have a contact name or number please??? - I am in Dover,Kent).

Cheers,
Andy Bowles.
 

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Originally posted by Atomic Badger:
[qb]My car is a 1994 2.3T CSE, tuned up (theoretical to around 260BHP with remapped ecu, bigger back box, no cat, dump valve, bleed valve etc.

Only say all this to get onto the Toluene question.  Being a non-technical bod, should I buy the stuff and put it in for road use, and if so what would be the upper safety/sensible percentage limit ??

Also, in laymans terms what will it do for me sitting behind the wheel ??

Finally, who sells it please ??
(Simon - you can get it for £18 per 5 gallons, do you have a contact name or number please??? - I am in Dover,Kent).

Cheers,
Andy Bowles. [/qb][/b]
The upper safety limit for Toluene would probably be about 1/3 the voume of your tank. Possibly up to 1/2, but that's REALLY pushing it.

For road use it's certainly not a BAD idea ... but only if you wish to spend the extra dosh. It's not usually necessary.

Sitting behind the wheel ... if your ignition is retarded, or boost retarded, due to low octane, it will advance, and you'll get more :fawly: ...

... if not ... then you won't feel much difference at all except on the hottest days. Just try it once and see.

As for locating it, it's used as paint thinner, and can be located at many professional paint stores in fair quantities. Though also chemical supply warehouses frequently stock it.

Just make sure it's pure, wherever you get it from.

Dubbya~
 

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Adrian W.

Thankyou for info.

I usually use around 97 or 98 RON Fuel, so with a 3rd of a tank that would push it up around 104-105 RON. I assume it should not be much higher than this.

What does "ignition retarded" mean please ??

Thankyou,
Andy Bowles.
 

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Your car retards ignition timing when it detects knock due to low octane. If this is occuring, it will advance it when the knock is no longer there (IE when you have higher octane) ...

... also ... with 1/3 a tank of Toluene if you use 97 RON, you'd end up with 105 RON octane.

Dubbya~
 

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Originally posted by scminks:
[qb]i put some in (25% ratio)after my last post and its made a big difference.    :fawlty:        :thumbsup:    
simon [/qb][/b]
Good to see it's making a noticable benefit for you.


I haven't found a reasonable supplier of Toluene near where I live, so I use Xylene as a substitute. It's slightly higher octane, but must be used in smaller quantities. I only use two US gallons out of a 17 US gallon tank in the Viggen.

That's about 12% by volume. It makes a huuuuge difference in warm weather, but almost no difference in cold weather.

Since it's summer now, and the temps are currently (as I speak) in the 100+ (about 38 degrees C) range I'm enjoying LOTS of extra
that I wouldn't normally have any of!


Toluene is "better" than Xylene despite being slightly lower in octane, but if you can't find Toluene it's more than adequate!

Just make sure whichever you get is 100% PURE !! Most thinners are, because they're meant to evaporate eventually. But if it doesn't say it's pure Toluene or Xylene, don't get it!

Dubbya~
 

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Not wishing to be a killjoy, but the HMC&E view is that anything used as road fuel attracts road fuel duty in the UK.

I'm sure we all know about "red diesel", but do you remember the South Wales sunflower oil story ?

Biofuel story

Something there for the woodburners too
 
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