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Can I add Xylol (Xylene) to boost octane?

edited November -1 in Repair and Maintenance
A recent question about octane and a visit to a paint store made me wonder:



Can I add Xylene to my gas tank to boost octane? My car calls for 89 or better octane, but I can usually get away with using 89 every second or third fill-up without getting noticeable spark knock. On the rare occasions I've filled with Sunoco 93 octane fuel, I can smell xylol as I'm filling my car. I know that it is one of many additives that boost octane. (by making gasoline burn somewhat slower)



Can I add pure xylene to my tank to boost octane? Do you think it would harm a catalytic converter or oxygen sensors? What would be the recommended percent to add to increase octane a couple of points?



Anyone with some knowledge of chemistry have any input?
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Comments

  • edited May 2009
    Yes, you can. You've discovered the secret to boosting octane. You sly bastard! The government will soon be sending someone to pick you up. You will likely be tortured at Gitmo, or perhaps somewhere in the middle east. Egypt?

    Sorry, we don't torture. My mistake.

    Be that as it may. If the government doesn't pick you up the oil companies will, and they're WORSE. I'm glad I'm not you, oblivion. I wish you the best of luck. I suggest running NOW, before they get your location.

    Too late, they already have it.

    You have opened a very dangerous can of worms. They will be looking for you. They will find you. You can't hide. You have exposed the Xylol (Xylene) conspiracy. God help you.
  • edited May 2009
    PS

    You're a cheapskate. If your vehicle needs 89 or better then you should feed it 89 or better.

    There are no products that will make up the difference.
  • edited May 2009
    Xylene may damage the polymer products it comes in contact with. I'd be very careful with it. It severely attacks virtually any elastic product, such as nitrile, latex, silicone, and urethane. Gotta rubber hose? It's gone if you use xylene, and how will the dissolved rubber affect your other components?
  • edited May 2009
    lol... actually I'm not a cheapskate. I feed it what it needs. But if the oil companies actually add xylene as an additive to boost the octane, then sell it at a 20? premium per gallon, why shouldn't I buy a can of pure xylene and do the same? It's no worse than folks with diesel cars using old fryer oil in their tanks to save money. If I add an aftermarket octane booster and my spark knock goes away, it's demonstrably proven that there are "products that will make up the difference"
  • edited May 2009
    Obviously, that is not the case as you said

    " My car calls for 89 or better octane, but I can usually get away with using 89 every second or third fill-up without getting noticeable spark knock"

    Use the fuel that your owner's manual requires. I'm sure spending the extra $2 per fill up won't bankrupt you.
  • edited May 2009
    I intend to keep using the 'correct' fuel for my car unless I have a reason to do otherwise, and obviously the $2 per fill up won't bankrupt me. And as many have stated in this forum, use the lowest octane that your car will run well on, and there's no benefit in using higher octane than this. Filling up every-other time with 89 when my car runs fine this way seems to me to be just being intelligent about it, not cheap.

    However, my question was is it possible to use xylene as an octane booster, and what if any consequences should I expect. Telling me to use the fuel that the owner's manual specifies does not answer my question. So far, jtsanders has come closest to a useful comment, no offense intended.
  • edited May 2009
    Ok, I'm still curious as to what everyone has to say, but after a web search, I'm not nearly the first to have thought of this. Many racers have been doing this forever to boost octane. There are various formulas for homebrew octane boosters containing xylene, toluene, and other solvents. Apparently the key is to not get too carried away and to use a lubricating agent such as Marvel mystery oil or a couple of ounces of two-cycle oil or kerosene. This supposedly will help protect rubber components and other 'edibles' in the fuel system. After some searching, apparently many gasolines already contain methanol, ethanol, and/or mixes of xylene, toluene, and other chemicals that are already somewhat bad for rubber and plastic components, and emission control sensors. Based on the price of xylene and the amount of octane gained, it would probably be worth doing to boost octane a little cheaper than shelling out for premium, but only slightly when you factor in the bother of mixing it. So I've kinda answered my own question. But I'm still interested in anyone's viewpoint. If you're interested, here's the Google search:

    http://www.google.com/search?q=xylene+as+octane+booster&hl=en&lr=&start=0&sa=N
  • edited May 2009
    "After some searching, apparently many gasolines already contain methanol, ethanol, and/or mixes of xylene, toluene, and other chemicals that are already somewhat bad for rubber and plastic components, and emission control sensors."

    This sounds like BS to me..Could you source these statements?
  • edited May 2009
    Everything comes with a price so I guess you can steal the Xylene somewhere. Maybe you can read the MSDS to check for the hazards of handling it too. Who knows? It may have drawbacks.
  • edited May 2009
    You want miracle gas additive? Here you go:

    Acetone.

    It's just as good, if not better than, what you're proposing.

    Operative word here is: SCAM.
This discussion has been closed.