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STP

STP Octane Booster for Gasoline Fuel Additive, 5.25 oz, Fuel Additive That Raises Octane Levels and Cleans the Fuel Intake System to Restore Lost Power and Acceleration, Help Improve MPG

  • Based on 1,228 reviews
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Availability: Only 6 left in stock, order soon!
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Arrives Wednesday, Sep 24
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Size: 5.25 Fl Oz (Pack of 1)


Features

  • OCTANE BOOSTER FOR GASOLINE: One 5.25 bottle of STP Octane Booster, a 2-in-1 fuel additive featuring MMT + Synthetic Technology to boost octane and clean the fuel intake system, restoring lost power and acceleration
  • COMPATIBLE WITH CAP-LESS SYSTEMS: This fuel treatment is compatible with all gasoline engines, including cap-less gas systems
  • RAISES OCTANE LEVELS: MMT, a powerful gas additive, raises octane levels to reduce knocking and pinging caused by combustion chamber deposits that increase your engines need for higher-octane fuel
  • CLEANS THE FUEL INTAKE SYSTEM: The Synthetic Technology in this gas treatment helps clean the fuel intake system, improving fuel flow and combustion efficiency for smoother acceleration and increased horsepower
  • HELPS IMPROVE MPG: Made with jet fuel, a high-quality carrier of active ingredients, STP Octane Booster helps improve MPG by optimizing fuel use and reducing engine strain
  • USE WITH EVERY FILL-UP: Use the gasoline additive regularly when you fill up your tank; simply pour the entire contents in your gas tank before or after fueling (one 5.25 fl oz bottle treats up to 15 gallons of gasoline)

Description

Give your engine the boost it needs with STP Octane Booster for Gasoline, a 2-in-1 fuel additive featuring MMT + Synthetic Technology to boost octane and clean the fuel intake system, restoring lost power and acceleration. This fuel treatment is compatible with all gasoline engines, including cap-less gas systems. MMT, a powerful gas additive, raises octane levels to reduce knocking and pinging caused by combustion chamber deposits, which can increase your engine’s need for higher-octane fuel. The Synthetic Technology in this gas treatment helps clean the fuel intake system, improving fuel flow and combustion efficiency for smoother acceleration and increased horsepower. Made with jet fuel, a high-quality carrier of active ingredients, STP Octane Booster helps improve MPG by optimizing fuel use and reducing engine strain. Use the gasoline additive regularly when you fill up your tank. Simply pour the entire contents in your gas tank before or after fueling. One 5.25 fl oz bottle treats up to 15 gallons of gasoline. Unleash your engine's true potential with STP Octane Booster.

Manufacturer: ‎STP


Brand: ‎STP


Model: ‎78574


Item Weight: ‎5.5 ounces


Product Dimensions: ‎1.5 x 2.3 x 8 inches


Country of Origin: ‎USA


Item model number: ‎78574


Is Discontinued By Manufacturer: ‎No


Exterior: ‎[[Not Applicable]]


Manufacturer Part Number: ‎78574


Position: ‎Outside


Voltage: ‎12 Volts


Date First Available: February 4, 2011


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Wednesday, Sep 24

This item is non-returnable:

Non-returnable. Transportation of this item is subject to hazardous materials regulation

View our full returns policy here.

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Top Amazon Reviews


  • This will NOT increase hp, torque, or speed
Size: 5.25 Fl Oz (Pack of 1)
Do not buy this if you are thinking it will improve your vehicle's performance in some way. I made that mistake of ignorance myself when first grabbing a bottle off the gas station shelf. It likely won't hurt your engine to use one bottle per 15 gallons (they say up to 20), but it's just not what most people think it is/does. **edit*- this DID cause transmission damage, knocks, and pings on my naturally aspirated system. I mistakenly thought that my variable octane (87-93) engine and drive train could handle this change in octane. This was my mistake, I was wrong, and this shouldn't be used on a naturally aspirated engine unless the gas has been sitting for ~6 months and has gone stale. Check with your dealer about your specific vehicle make & model.* Octane boosters raise the octane level of your fuel, making it MORE difficult for gasoline to combust under pressure. They get a bad rap as they're sold as performance enhancers, or speed boosters. High-revving, high psi turbo/supercharged engines can benefit from this as it leads to increased efficiency of combustion. High-octane fuel requiring performance cars that only have access to 87 octane gas stations, or fuel that's been sitting around a few months or more can benefit from this too. You can do some research yourself, but if your vehicle does not specifically recommend using an octane booster or a fuel with octane higher than 91 or 93, then it's likely not for you. Maybe if you only have access to low octane gas, but this is an expensive way to boost it by only a little. You're way better off using 93, or 91 octane as your car will take. Using with regular gas if your car takes regular 87 octane gas will do nothing. I use it in a naturally aspirated 3.8L V6 with 104k miles and it was what was causing me knocks around 3rd gear. Typically a fuel system cleaner (and this part is important!) which SPECIFICALLY lists the detergent levels, not just the name of the chemical the detergent used, is a better bet for increasing performance, but still only by a few hp in the best of scenarios on the oldest of cars in the worst of shape over a long time after a lot of uses, and typically is only around up to 0.5hp. This one doesn't even list the detergent I don't think, just that it has 'jet fuel' whatever tf that actually is. It's not fuel for a jet, that's for sure (kerosine is what jet fuel actually is). There are way way better options for boosting performance, and I'm not sure how this would handle in a system that can't take varying levels of octane. Snake oil for many, but it does have it's uses and works for some very specific cases and again, it does not make sense to me yet why. I have some unknown issue, in a 3-year-old car with a ton of miles for the years, which can take variable octane fuels. I likely have some hairline crack in my fuel system somewhere leaking vapor or letting moisture in. **edit*- it was this octane booster which was contributing to my tranmission knocking issue. After stopping use and going down in fuel grade for a month, it's running like new again.* ... show more
Reviewed in the United States on December 26, 2022 by Snake Plissken

  • Stp treatment
Size: 5.25 Fl Oz (Pack of 1)
Great additive to vehicle.
Reviewed in the United States on April 6, 2025 by reginald f.

  • Seemed to work
Size: 5.25 Fl Oz (Pack of 1)
seemed to work. used monthly to hopefully keep fuel system clean, was a subscribe and save item until substantial price increase then dropped item. if price drops to where it was I would resubscribe
Reviewed in the United States on September 29, 2024 by E. H. Anderson

  • More power! Less mileage because it's too much fun.
Size: 5.25 Fl Oz (Pack of 1)
First and foremost, your engine needs a knock sensor to get any benefit from this. If it's not a performance car, it's probably tuned for 87 and may run worse if you add this. If you don't know whether it has a knock sensor, Google it. I added it to a tank of 91 octane gas, and my engine immediately responded with more torque. It was noticable. Not like adding a supercharger, but you can tell it's pushing a few more pound-feet of torque. I suppose this could boost mileage, but it just makes it so much fun to floor the accelerator... I will say that if I go on the freeway and reset the counter, and there's not much traffic, it'll read 35MPG with the air conditioning on all the way until I exit, even if that's 50 miles later. This is in a heavy Acura TL-S with a 3.5L V6. That might be two or three higher than usual. As for city driving, it's worse because, again, it just invites me to accelerate more quickly. Someone with a gentler touch might get better city mileage than me. Hard to say. I make mostly short trips on surface streets, so my mileage is going to be awful most of the time. ... show more
Reviewed in the United States on September 16, 2023 by Horst Enthusiast

  • My favorite Octane Booster!!!
Size: 5.25 Fl Oz (Pack of 1)
Using in a 16 year old Lexus and has improved MPG and lost power. Only using every 3rd fill up with REG gasoline 87. Recommended for all V6 engines as also tried in a Ford, Dodge and other Lexus models.
Reviewed in the United States on January 12, 2025 by Jeff Moore

  • work well
Size: 5.25 Fl Oz (Pack of 1)
i put this in my fuel cell to help with fuel storage
Reviewed in the United States on February 16, 2025 by tb23498

  • This is a great octane booster
Size: 5.25 Fl Oz (Pack of 1)
This is a great octane booster and it was able to keep my car running great but once they got ridiculous and made it so you couldn't buy single bottles or even buy six bottles you have to buy 12 bottles or more so I switched to a different company that completely destroyed my vehicle this is a great octane booster what worth well worth the money it's just that it's upsetting that you can't get it in smaller package deals ... show more
Reviewed in the United States on September 1, 2024 by Lance Gouvan

  • be careful
Size: 5.25 Fl Oz (Pack of 1)
Be careful of this one. Make sure you notice the ounces! You can buy the larger one at Meijer usually for a small difference and get a lot more. It looks like its a deal if you buy this until it's delivered and now you see the quantity is so much smaller than what you may be use to purchasing.
Reviewed in the United States on January 2, 2025 by Eric Bitzer

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