I gas up all our cars at the nearby Costco. We only have 91 octane here in California. I’d like to bump it up to at least 93 octane for one of my cars. I see so many different brands on the shelves. Any recommendations?
Inexpensive octane boosters from the local auto parts stores and Walmart
- Thread starter Nicasio
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Try to buy toluene by the gallon.
The stuff at the auto part stores is very diluted, I don't think it'd make a difference.
I’d like to bump it up 2 points for about 10 gallons. None of those boosters would work? 
Lacquer thinner?
Toluene or Xylene.
What car is this intended for? And what are you trying to achieve by boosting your octane?.
It's true that we don't have 93 in California but we do have racing gas which is 100 octane. Its much more expensive and unless you are racing, there is not much point in doing it.
I usually get gas for my Mercedes at Costco and I wanted to see what 100 octane would do and to be honest with you I couldn't really tell any difference.
VP Racing Fuel Street Blazer 100 octane should be available near you, give it a try and you might see something.
I just don't like cheap octane boosters sold at your random convenience store.
It's true that we don't have 93 in California but we do have racing gas which is 100 octane. Its much more expensive and unless you are racing, there is not much point in doing it.
I usually get gas for my Mercedes at Costco and I wanted to see what 100 octane would do and to be honest with you I couldn't really tell any difference.
VP Racing Fuel Street Blazer 100 octane should be available near you, give it a try and you might see something.
I just don't like cheap octane boosters sold at your random convenience store.
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My ‘85 Mustang/‘04 Cobra swap was dyno tuned on 93 octane. I don’t really smash on it, just cruisin most of the time, but I really want to be safe for when I do get on it.
I use this but make sure it is 50/50 xylene/toluene. Kleen Strip is the brand I use and their new, cheaper, greener stuff is not and looks like methanol and other solvents. They still have the 50/50 stuff. I use it as a fuel system cleaner though.
My local walmart carried VP Octanium, that would do what you want. They make 2 versions of it so make sure you get the one that is safe for cats.I’d like to bump it up 2 points for about 10 gallons. None of those boosters would work?
I use Boostane for mine.
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Isn't the rule of thumb that if you have 91 and want to achieve 93 you add e85?
EDIT: Had to go check my tuner, but they tuned my car for 93 (by default its 87, and they offer a 91 tune also).
"You may use a 93 octane tune if you plan on running 91 octane + 1.5 gallons of ethanol to increase octane."
EDIT: Had to go check my tuner, but they tuned my car for 93 (by default its 87, and they offer a 91 tune also).
"You may use a 93 octane tune if you plan on running 91 octane + 1.5 gallons of ethanol to increase octane."
It does seem that Cali does not allow 93 octane. Is the some reason for it? The owners manual for the Chevy 6.2 engine specs 93 octane.
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imho there is no benefit to 93 over 91. But I get your point, you pay way more for your fuel and you get less. But if you buy an additive, now you're really paying more and just burning up money out your tailpipes. my .02
Out east you'll see skimmers like Wawa selling 92 at 93 prices. Have to subsidize Hoagiefest somehow.
Out east you'll see skimmers like Wawa selling 92 at 93 prices. Have to subsidize Hoagiefest somehow.
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There isn't a benefit TO YOU.
The difference on my tune from 91 to 93 is 14 horsepower and 12lbft of torque across the entire rev range.
Toluene in modest quantities is superb for boosted engines. Not quite as good for normally aspirated engines, especially when cold out. If you choose to try it, purchase it from professional chemical/paint supply house. Otherwise you may get some form of adulterated product.
The VP stuff probably contains MMT, which will increase octane nicely, without causing operational issues during cold weather.
The VP stuff probably contains MMT, which will increase octane nicely, without causing operational issues during cold weather.
I used the Gumout Octane booster on my Volvo Turbo car. I normally just add 1/3 of the bottle to 18 gallons.
There is if you are tuned for 93 octane. More and more newer engines actively adjust timing to the point of detonation, so higher octane = more power in those engines that can sense what is in the tank.
Octane booster alone won't do anything unless timing is adjusted to take advantage of it.
I see that Metco idler pulley on there, are you pulleyed up? I used to run a 10lb lower and a 2.8 upper back when I had the Eaton M112 (Lightning conversion) on my truck. I've since gone to a Whipple 2.9 though.
I would look into Boostane if I were you, I run the marine version of it and it only takes .4 ounces per gallon to take me from 93 to 99 octane. Bootane has a mixing chart on their website. https://boostane.com/pages/boostane-mixing-chart
It takes .17 ounces per gallon to go from 91 to 94.
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