Pain at the pump octane boost

[Shadowcatche]

It is becoming increasingly painful to fill the tank in my Outback with a 3 L H6 which wants premium but gets mid grade.
I started looking into octane boosters and specifically going after the MSDS sheets to find out exactly what is in each of them. The main ingredient usually 98.5 to 90%, is kerosene. The rest is usually MMT Methylcyclopentadienyl manganese tricarbonyl or in a few cases ferrocene, both without going in to the chemistry, manganese. It is not economically advantageous to use a commercial octane booster, cost eats up the difference.
It would appear that kerosene alone is an octane booster and I use K1 kerosene to heat the garage during the winter using an Eberspacher diesel heater.
A will kerosene harm any of the components in the engine?
B is there a way to tell if it's working, the engine management system keeps it from pinging no matter whether I use regular, midgrade, or premium gas. My thoughts being monitoring some aspect of the OBD II with a scan gauge or OBD scanner.

[rough road]

shadow, three weeks ago we traded our Forester XT, premium gas needed, for a new OB with the cvt and it sure is nice to be able to put regular regular in it..., we feel your pain. Have you tried regular in the six ?, I cannot imagine it being a huge problem in a non turbo car, especially if your driving is on the restrained side.

[HMXDave]

As an avid snowmobiler and ATV rider, I have several small motors that will not survive on regular gasoline. You are 100% correct that the cost of octane boosters offsets the costs of just going to premium fuel. MOST octane boosters aren't worth the container it comes in. When they advertise that it "raises octane XX points"...it is DECIMAL POINTS, not full octane numbers. A few years ago, a few freinds and I decided to blend our own fuel. Now we were taking premium fuel and going to 96 to 100 octane, but the same would apply to taking regular and going to premium. Anyways....we ended up blending about a gallon of toluene, and a gallon of xylene to 8 gallons of premium. This gave real octane boost increases. (As you can see, a small bottle of magic octane booster really isn't going to do much) Due to the dangers of handling xylene and toluene, we gave up on it and most of us have detuned our motors to survive on a blend of race fuel and premium, or AV gas (LL100) and premium. AV gas is no good for modern cars as it has lead in it still.

Bottom line: I would bite the bullet and burn premium if it will hurt the motor running poor fuel. OR: see if the machine can be programmed with lower timing (and lower performance) to allow the use of lower grade fuel.

http://en.wikipedia.org/wiki/Octane_rating

[Ray,IN]

Perhaps new engines are different, but in the 90's diesel fuel/kerosene was not compatible with gasoline engines fuel seals, likewise gasoline was not compatible with seals in a diesel fuel system. That would be a question for a Subauru service manager.

[HMXDave]

Kerosene or ATF is added to many "octane boosters" as filler and because octane boosters are very dry. We ran our toluene/xylene concoction on two-stroke motors and always upped the oil usage a bit.

Edit: I found an old blending formulation. I'll paste it here as information, but I honestly do not recommend handling any chemical with an "ene" at the end of it. (Note: R+M/2 is research octane + motor octane / 2....which is how octane is reported at most pumps)

FORMULA 1
Toulene
R+M/2...114
Cost...$2.50/gal
Mixtures with 92 Octane Premium
10%...94.2 Octane
20%...96.4 Octane
30%...98.6 Octane
Notes: Common ingredient in Octane Boosters in a can. 12-16 ounces will only raise octane 2-3 *points*, I.e. from 92 to 92.3. Often costs $3-5 for 12-16 ounces, when it can be purchased for less than $3/gal at chemical supply houses or paint stores.


FORMULA 2
Xylene
R+M/2...117
Cost...$2.75/gal
Mixtures with 92 Octane Premium
10%...94.5 Octane
20%...97.0 Octane
30%...99.5 Octane
Notes: Similar to Toulene. 12-16 ounces will only raise octane 2-3 *points*, I.e. from 92 to 92.3. Usually mixed with Toulene and advertised as *race formula*.

FORMULA 3
Methyl-tertiary-butyl-ether (MTBE)
R+M/2...118
Cost...$3.50/gal
Mixtures with 92 Octane Premium
10%...94.6 Octane
20%...97.2 Octane
30%...99.8 Octane
Notes: Oxygenate. Very common in octane booster products. Has lower BTU content than toulene or xylene, but oxygenate effect makes the gasoline burn better and produce more energy.

FORMULA 4
Methanol or Ethanol
R+M/2...101
Cost...$0.60 - $1.75/gal
Mixtures with 92 Octane Premium
10%...94.3 Octane (Methanol)
10%...94.7 Octane (Ethanol)
20%...Not Recommended
Notes: Methanol is wood alcohol. Ethanol is grain alcohol and found in Gasohol in 10% ratios. Both alcohols are mildly corrosive and will eat gas tank linings, rubber and aluminum if used in excessive ratios. Main ingredient in "Gas Dryers", combines with water.

FORMULA 5
Isopropyl Alcohol and Tertiary Butyl Alcohol
R+M/2...101
Cost...$0.60-$1.50/gal
Mixtures with 92 Octane Premium
10%...94.5 Octane
20%...Not Recommended
30%...Not Recommended
Notes: Similar to Methanol/Ethanol. Isopropyl Alcohol is simply rubbing alcohol.

[Ray,IN]

This is kinda off-topic but seems relevant. The EPA has a proposal to blend Ethanol into diesel fuel. I haven't read anything further for about 6 months, but I suspect that would kill older diesel engine fuel systems.
OK, back to gasoline octane requirements for certain engines. If your engine requires premium and you run in on a lower grade gas, sure the ECM will compensate as much as possible to reduce engine damage. It cannot eliminate engine damage even though it reduces effects of the lower grade.

[Chuck 1935]

If it says use PREMIUM do it. The repairs will far outweigh any price advantage.

[lllkrob]

As a powertrain systems engineer for a major automotive manufacturer, I can assure you your engine will perform satisfactorily on 87 octane unleaded regular. You may notice a very slight loss in power and mileage but the engine will not be damaged. Today's vehicle engine management systems will re-map all the operating parameters to account for the loss of octane. The premium fuel " requirement " is so the engine will perform at optimum levels and fuel mileage.

[Chuck 1935]

Originally Posted by lllkrob

As a powertrain systems engineer for a major automotive manufacturer, I can assure you your engine will perform satisfactorily on 87 octane unleaded regular. You may notice a very slight loss inpower and mileage but the engine will not be damaged. Today's vehicle engine management systems will re-map all the operating parameters to account for the loss of octane. The premium fuel " requirement " is so the engine will perform at optimum levels and fuel mileage.

MAJOR CAVEAT : If you don't have Todays systems you could have problems and your fuel milage could be adversly affected.

[TW]

We always filled our MB with Regular Gas. On the Autobahn in Germany the Difference was not noticeable. They all run way over 120 Miles/h or over 200 kmh. Even on HLN Clark Howard said drive Regular. I did it for years, but after Warranty time!

TW

[Dirtbuster]

My BMW says Premium only, as in 93 octane. Anything less, & she don't run or idle correctly. When she don't run right, she gets very expensive.

Only the good stuff for her!

[lllkrob]

The OP stated he had a Subaru Outback with a 3.0 liter H6 engine. This engine was introduced in Subaru vehicles in 2004 and is fully OBDII compliant. Therefore it will run on 87 octane unleaded fuel without engine damage. It is one of TODAYS engines.

[TW]

All our Rental cars get Reg, even it is a Premium gas engine. Noway do I put that stuff in a Rental car. My own cars liked it and here in Canada I just drive the speed limit, but not on the Autobahn
BMW cuts out at 250 kmh and we always reach it. OK - we slow down to 249 kmh

TW

[Meandering Retiree]

Our Mini Cooper "requires" premium...I filled it with regular and quickly figured out that running premium costs me less than 1 cent a mile more per mile and the engine runs better and much more powerfully. Just my 2 cents worth. :-)