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i have a 00 zetec with cat-back custom exhaust,plugs will runing 93 otcane with octane boaster give more hp???? or will it harm it????
 

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it will either do nothing or harm it. there is no question, it will not help. SOME people get a smoother idle from running 89, but not everyone. i dont. you will gain nothing from running 91, 93, or 93+ (my god, stop wasting your money
)
 

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All high octane does is burn slower. It has additives that burn slower than the gasoline itself. Higher octane will probably make you loose power. I'd run 89 if you want higher octane.
 

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Don't run 93 unless you have a chip. Like they said, higher octane gas burns slower, it'll hurt ur engine more than enhance performance.
 

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"Higher octane fuel burns slower" is a wive's tale. It might or might not. There is no correlation between octane rating and rate of burn.
 

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Well you'll get better gas milage...so it's actually cheaper in the long run. and regular unleaded is worse for newer cars than premium. It's worth it. My focus loves running it.
 

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I've calculated my mileage per dollar of 87 and 91 and my car goes farther per dollar on 91. That is all.


g
 

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Myth about Premium Gas

Many people believe that "premium" gas is the best gas. Not true. Premium simply means "premium price" for higher octane. Octane is a simple measurement for a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders.

Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane) and premium (usually 92 or 93). The misnomer about octane is that the higher the rating, the better or more smoothly your car will run. In fact, premium gas can be bad for your engine if it was not designed to run at a high-octane level.

Although it may seem that the term "premium" or "high octane" implies that more energy is available, premium gas does not produce more energy than regular or mid-grade fuel. The octane grades are designed to accommodate engines with different compression ratios. High compression engines, found in most performance cars, require a fuel that burns efficiently at a higher temperature. That’s what premium fuel does, it burns hot under high compression. In a normal engine, premium fuel does not burn completely, resulting in excess carbon build-up and carbon fouling of the spark plugs.

The end result is a less efficient engine that requires tune-ups more frequently. Oh, yeah, did I mention it also wastes money?

The only time you might need to switch to a higher octane fuel is if your car engine knocks when you use the recommended fuel. This happens to a small percentage of cars. Check your owner’s manual to determine the right octane level for your car. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars and certain luxury cars, need mid-grade or premium gasoline to prevent knock.

Hope this answers some of your questions
 

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dan-d speaks the truth!

A gallon of 87 or 93 octane has the same amount of energy, roughly 114,00 Btu's per gallon (FYI diesel is about 128,00 Btu/gallon). The higher octane simply prevents detonation at high compression ratios (ie you turbo/supercharger people.
 

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Also, chips that advance your timing will require higher octane -- 89, or more often, 91 or 92, don't waste money on 93 or higher if all you have is a chip and bolt-ons without any work that would change the compression.
 

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let's answer the will higher octance burn slower thing. Get 4 jack stand... set yur car up on... set the cruise control to 35 or what ever speed you'd like, and just let it go. (use the odometer's trip set as your "results" then fill up with the other octane and repeat
 

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In a normal engine, premium fuel does not burn completely, resulting in excess carbon build-up and carbon fouling of the spark plugs.
and dead catalytic converters, perhaps?
 

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Higher octane does not produce hp, just prevents deto which in return helps your car right right when needed. Modified mag has a whole article explaining it. Check out the latest one.
 

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I know that higher octane in and of itself doesn't make more HP, but how does changing timing settings and then having to use premium fuel to avoid detonation, produce more power, or at least the feel of more power? I am thinking of the first mod I did to my 2000 ZX3 over 3 years ago which was to install a Superchip. The car did run better, with more power and response, after installing the chip so I know it did something.
Thanks for the feed back!
 

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Very Informative Excerpts. Check the American Petroleum Institute (API) for more information.

THE FACTS ON HIGH OCTANE GASOLINE

* Do you buy a high octane gasoline for your car because you want to improve its performance? *

The recommended gasoline for most cars is regular octane. In most cases, using a higher octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner’s manual.

* Does high octane gasoline increase power? *

If your car is designed to run on 87 octane gasoline, you shouldn't notice any more power on high octane gasoline. If it does make a noticeable difference, you may need a tune-up.

* Does high octane gasoline improve mileage? *

In general, if your car is designed to run on 87 octane gasoline, high octane gasoline will not improve mileage. If switching to high octane gasoline does improve mileage, you might find that a tune-up will give you the same improvement on 87 octane gasoline.

* Does high octane gasoline achieve quicker starting? *

No, it doesn't.

* Will higher octane gasoline clean your engine better? *

As a rule, high octane gasoline does not outperform regular octane in preventing engine deposits from forming, in removing them, or in cleaning your car’s engine. In fact, the U.S. Environmental Protection Agency requires that all octane grades of all brands of gasoline contain engine cleaning detergent additives to protect against the build-up of harmful levels of engine deposits during the expected life of your car.

* Is high octane gasoline more refined -- is it just a better product? *

Additional refining steps are used to increase the octane; however, these additional steps do not make the gasoline any cleaner or better. They just yield a different blend of hydrocarbons that burn more slowly. The additional steps also increase the price.

* What are octane ratings? *

Octane ratings measure a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders. Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane) and premium (usually 92 or 93). The ratings must be posted on bright yellow stickers on each gasoline pump.

* What’s the right octane level for your car? *

Check your owner’s manual to determine the right octane level for your car. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars, old cars and certain luxury cars, need mid-grade or premium gasoline to prevent knock.

How can you tell if you’re using the right octane level?
Listen to your car’s engine. If it doesn’t knock when you use the recommended octane, you’re using the right grade of gasoline. Knock occurs when cylinder pressures are high. It is normal for an engine to ping a little at full throttle because cylinder pressures are very high at full throttle. Engine knock, however, should not be ignored since it can result in serious damage to the engine. High octane gasoline burns slower than low octane gasoline. The slow burn prevents engine knock when cylinder pressures are high.

If your engine runs well and does not knock or ping on low octane gasoline, there is no advantage in switching to higher octane gasoline.
 

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Very Informative Excerpts. Check the American Petroleum Institute (API) for more information.

THE FACTS ON HIGH OCTANE GASOLINE

* Do you buy a high octane gasoline for your car because you want to improve its performance? *

The recommended gasoline for most cars is regular octane. In most cases, using a higher octane gasoline than your owner’s manual recommends offers absolutely no benefit. It won’t make your car perform better, go faster, get better mileage or run cleaner. Your best bet: listen to your owner’s manual.

* Does high octane gasoline increase power? *

If your car is designed to run on 87 octane gasoline, you shouldn't notice any more power on high octane gasoline. If it does make a noticeable difference, you may need a tune-up.

* Does high octane gasoline improve mileage? *

In general, if your car is designed to run on 87 octane gasoline, high octane gasoline will not improve mileage. If switching to high octane gasoline does improve mileage, you might find that a tune-up will give you the same improvement on 87 octane gasoline.

* Does high octane gasoline achieve quicker starting? *

No, it doesn't.

* Will higher octane gasoline clean your engine better? *

As a rule, high octane gasoline does not outperform regular octane in preventing engine deposits from forming, in removing them, or in cleaning your car’s engine. In fact, the U.S. Environmental Protection Agency requires that all octane grades of all brands of gasoline contain engine cleaning detergent additives to protect against the build-up of harmful levels of engine deposits during the expected life of your car.

* Is high octane gasoline more refined -- is it just a better product? *

Additional refining steps are used to increase the octane; however, these additional steps do not make the gasoline any cleaner or better. They just yield a different blend of hydrocarbons that burn more slowly. The additional steps also increase the price.

* What are octane ratings? *

Octane ratings measure a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders. Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane) and premium (usually 92 or 93). The ratings must be posted on bright yellow stickers on each gasoline pump.

* What’s the right octane level for your car? *

Check your owner’s manual to determine the right octane level for your car. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars, old cars and certain luxury cars, need mid-grade or premium gasoline to prevent knock.

How can you tell if you’re using the right octane level?
Listen to your car’s engine. If it doesn’t knock when you use the recommended octane, you’re using the right grade of gasoline. Knock occurs when cylinder pressures are high. It is normal for an engine to ping a little at full throttle because cylinder pressures are very high at full throttle. Engine knock, however, should not be ignored since it can result in serious damage to the engine. High octane gasoline burns slower than low octane gasoline. The slow burn prevents engine knock when cylinder pressures are high.

If your engine runs well and does not knock or ping on low octane gasoline, there is no advantage in switching to higher octane gasoline.
Best first post ever!


That is pretty much dead on!
 

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Interesting, but I still don't buy it. This looks like a dumbed down consumer version of fuel info.

This info states "Octane rating measure a gasoline's ability to resist knock, a rattling or pinging sound resulting from PREIGNITION ..." In most cases that is not even the problem we are trying to avert by using high octane. We are more likely concerned with preventing DETONATION, an entirely different problem - one that can be aggravated or lessened by timing adjustments. PREIGNITION occurs before the spark event, and therefore is not be effected by it or knock sensor inputs. This info doesn't even acknowledge detonation. A small point, but one that indicates there was no intention of absolute technical correctness in this consumer info.

"Additional refining steps ... just yield a different blend of hydrocarbons that burn more slowly." "High octane burns slower than low octane. The slow burn prevents engine knock when cylinder pressures are high."

According to the technical info I have read in the past, this is incorrect as well. The ability to resist premature ignition (preignition), and burn in a controlled fashion while resisting undesired ignition from occuring at unplanned points during the burn (detonation) is what provides the knock resisitance - resistance to ignition. Maybe it would be more accurate to say "slower to ignite" instead of "burns slower"?


I have read it plainly stated in what appeared to be a reliable technical source that burn rate and octane are not related. This was backed to some extent by reading about some dyno testing with a high octane racing fuel that burnt faster than normal "Premium", presumably by design to deliver max energy when used in high RPM applications. It has been a while but I believe I also saw this on a Shell (UK?) consumer info page - might have been another oil company though.

I will stick to my "It may burn slower, it may not, the two are unrelated" statement. But I am open minded to change if reliable info is brought.
 

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if you put premium fuel in a car that doesnt have to run on it....you are a complete moron, every body who knows anything about anything knows that.

just throwing your money away
 

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The dealer told me not to run anything but 87 octane fuel. Emissions controls are designed to operate with 87 octane fuel. I use a non-alcohol based fuel conditioner frequently and see improved mileage, more consistant idle.
 
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