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With a stock engine it is best to use the octane grade of fuel recommended by the manufacturer. Gasoline has a fairly similar BTU value per gallon regardless of octane (unless it's oxygenated like VP2 or VP4). The higher octane does allow you to alter aspects of the engine such as CR and timing advance to produce more power because of its resistance to detonation/pre-ignition/detonation.
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Can you mix regular unleaded petrol and supreme unleaded in citroen xzara 2009 make?
Yes, you can mix fuels, but why do this. Use the exact octane fuel that is recommended by the manufacture. Using a higher octane fuel will provide no benefit whatsoever.
Why does your jeep Cherokee make a funny noise and knockin sound when pulling away?
the engine is knockinq due to low octane fuel. try a tank of higher octane or add some octane boost to what you now have and it should be good for a while.
Why do you use octane in vehicles?
Octane is a measurement of the combustion process. Most commonly you will see "85 87 91" octane ratings on your average gasoline pump, this of course indicates the amount of octane that, that specific product contains. The only purpose of octane is to resist detonation. What this means is that a higher octane gasoline is actually more stable than a lower rated fuel. When any kind of fuel is subject to high pressure and high heat (just like you'll find on the compression stroke of an average automobile) it becomes unstable and in some cases will spontaneously combust without an ignition source, this is called "detonation" which will make your engine sound like it's "knocking". Vehicles requiring a high octane fuel most often have engines with higher compression ratios which of course cause higher heat and higher pressures. Most common vehicles only require an octane rating of 85, octane ratings of 87 and 91 won't make your car run any better.
What are the effects in the engine when using high octane gas?
Octane cannot be seen, but it is of utmost importance when it comes to gasoline. One thing for sure, higher octane fuel costs a lot more. Simply put, octane is a measure of gasoline's ability to resist detonation, which you hear as pinging and knocking in your engine. The higher the octane the more the fuel can be compressed without detonating before you want it to. Detonation, ping, knock, whatever you want to call it, occurs when the air/fuel mixture ignites before the spark plug fires. The mixture ignites from compression and not from the flame of the spark plug. In other words, the higher the octane the less likely it is to ignite prematurely. The only benefit to a high octane fuel is that it allows an engine to run at a higher temperature and with a higher compression ratio without pinging. Higher octane fuel does not provide more energy, more power, better mileage, more torque, burn cleaner, clean your engine, and is not better for the environment. If the engine is pinging when using the correct octane fuel, then it may be necessary to move to the next higher octane to prevent pinging, and damage to your engine, unless there is another problem. If you are using higher octane fuel for any of these reasons, STOP, you are throwing your money away. Also, never use a lower octane fuel than is recommended by the manufacturer. If the manufacture recommends 89 octane then use 89. If they recommend 87 then use 87. The key is knowing what was the engine designed to run at to achieve optimum performance and mileage. One exception is when you are towing a heavy load with a vehicle designed to run on 87 and you experience pinging. In that case it may become necessary to switch to 89 while towing. In conclusion, race car engines are designed to run on high octane fuels due to their high compression engines. You cannot make your engine a race engine just by upping the octane. Save your hard earned money, and use exactly the octane you need. <<>> Octane C8H18 can be mixed with heptane C7H16 to form petrol (gasoline). Heptane being a less-heavy molecule has a lower ignition temperature. An octane rating of 95 gives the same ignition temperature as a mixture of 95% octane and 5% heptane. Higher-octane fuel detonates at a higher temperature. High-octane fuel can be used in an engine with a higher compression-ratio to produce more power. The extra power comes from the compression ratio and the higher thermodynamic efficiency, rather than any change in the chemical energy in 1 kg of fuel. In earlier days high-octane petrol was reserved for aero-engines so motorists had to use the lower octane stuff and tolerate an engine with a lower compression ratio producing slightly less power for its cubic capacity.
Does it help to use octane rated higher than your vehicle requires?
No. * Added - Unless you are prepared to modify the tuning of your engine, the recommended octane rating is the best. Higher octanes do not provide more power, they simply burn slower. The higher the octane, the harder it is to ignite, which in most cases, will have no effect, but can make make the car harder to start. If you have an older car and have the equipment to adjust your vehicles system, using a higher octane fuel can result in higher gas mileage and more power. It requires that the spark timing be advanced to begin burning slightly sooner - and if a lower octane is then used with the same set-up, it can destroy the engine.
Why would we not crack octane industrially?
Octane is very useful the way it comes, and the lower alkanes you could crack octane into are plentiful. Cracking is a good technique for converting bitumen into an alkane that fuel can be made from, but you can make fuel (specifically gasoline) from octane.
What is the difference between 87 and 93 gasoline?
: Fuel octane requirements for gasoline engines vary with the compression ratio of the engine; Engine compression ratio is the relative volume of a cylinder from the bottom most position of the piston's stroke to the top most position of the piston's stroke. The higher an engine's compression ratio, the greater the amount of heat generated in the cylinder during the compression stroke. Posted octane numbers on gasoline pumps are a result of testing fuel performance under laboratory and actual operating conditions. The higher the octane rating on fuel the less volatile (evaporative qualities) and the slower the fuel burns. Higher octane fuel contains more POTENTIAL energy but requires the higher heat generated by higher compression ratio engines to properly condition the fuel to RELEASE that higher potential energy. In the refining process, fewer gallons of higher octane fuels are yielded from a barrel of raw crude, thus the higher cost. If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODESrather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation. Many vehicle owners believe that higher octane fuels are better for their vehicles since they are labeled "PREMIUM." The logic is that since it is a premium fuel it must be better. In reality, the premium label originates from the higher cost to refine and the resultant higher retail cost. Some refiners label their high octane fuels "SUPER." Some owners think that these fuels will make their vehicles more powerful. This is a MYTH! Only engines with high compression ratios can deliver all the potential energy from higher octane fuels! Always consult the manufacturer's octane recommendation to determine the proper octane requirements for any given vehicle. Generally, engines with compression ratios of 9.3 : 1 or less will safely operate with unleaded 87 octane fuel. Engines with higher compression ratios usually require higher octane fuels. But many modern engines will safely burn 87 octane even with a higher compression ratio. This is accomplished by way to the engine fuel/air management system. Many owners who operate vehicles designed to operate on 87 octane fuel experience ping and knock. They usually "fix" this problem by purchasing the higher priced, higher octane fuels. Most owner's manuals indicate that some light and intermittent ping is normal but that heavy or sustained ping or knock should be attended to by either purchasing the correct octane fuel or servicing the engine. Most fuel refiners blend fuels for geographic areas and adjust their blends seasonally. These blending techniques compensate for the decrease in oxygen content with an increase in altitude and compensate for volatility during the warmer or cooler seasons. Significant ambient temperature changes (40 degrees Fahrenheit) or altitude changes (4,000 feet) may cause some serious engine detonation. This problem is usually corrected by filling the tank with "local" fuel that has been properly blended for season and altitude. Bottom line is do not waste your money on a fuel with a higher octane than your engine requires. You reap no benefits, and are just wasting money.: Fuel octane requirements for gasoline engines vary with the compression ratio of the engine; Engine compression ratio is the relative volume of a cylinder from the bottom most position of the piston's stroke to the top most position of the piston's stroke. The higher an engine's compression ratio, the greater the amount of heat generated in the cylinder during the compression stroke. Posted octane numbers on gasoline pumps are a result of testing fuel performance under laboratory and actual operating conditions. The higher the octane rating on fuel the less volatile (evaporative qualities) and the slower the fuel burns. Higher octane fuel contains more POTENTIAL energy but requires the higher heat generated by higher compression ratio engines to properly condition the fuel to RELEASE that higher potential energy. In the refining process, fewer gallons of higher octane fuels are yielded from a barrel of raw crude, thus the higher cost. If fuel octane is too low for a given compression ratio, the fuel prematurely and spontaneously ignites too early and the fuel charge EXPLODESrather than BURNS resulting in incomplete combustion. The net effect is a loss in power and possible engine damage. The operator hears an audible "knock" or "ping", referred to as detonation. Detonation may vary from a faint noise on light acceleration to a constant, deep hammering noise while driving at a constant speed. Improper timing adjustments, vacuum leaks, or excessively lean fuel mixtures may also cause detonation. Many vehicle owners believe that higher octane fuels are better for their vehicles since they are labeled "PREMIUM." The logic is that since it is a premium fuel it must be better. In reality, the premium label originates from the higher cost to refine and the resultant higher retail cost. Some refiners label their high octane fuels "SUPER." Some owners think that these fuels will make their vehicles more powerful. This is a MYTH! Only engines with high compression ratios can deliver all the potential energy from higher octane fuels! Always consult the manufacturer's octane recommendation to determine the proper octane requirements for any given vehicle. Generally, engines with compression ratios of 9.3 : 1 or less will safely operate with unleaded 87 octane fuel. Engines with higher compression ratios usually require higher octane fuels. But many modern engines will safely burn 87 octane even with a higher compression ratio. This is accomplished by way to the engine fuel/air management system. Many owners who operate vehicles designed to operate on 87 octane fuel experience ping and knock. They usually "fix" this problem by purchasing the higher priced, higher octane fuels. Most owner's manuals indicate that some light and intermittent ping is normal but that heavy or sustained ping or knock should be attended to by either purchasing the correct octane fuel or servicing the engine. Most fuel refiners blend fuels for geographic areas and adjust their blends seasonally. These blending techniques compensate for the decrease in oxygen content with an increase in altitude and compensate for volatility during the warmer or cooler seasons. Significant ambient temperature changes (40 degrees Fahrenheit) or altitude changes (4,000 feet) may cause some serious engine detonation. This problem is usually corrected by filling the tank with "local" fuel that has been properly blended for season and altitude. Bottom line is do not waste your money on a fuel with a higher octane than your engine requires. You reap no benefits, and are just wasting money.
What is the recommended fuel octane for a Yamaha enticer 340?
their really is not a specific fuel octane mix. if you just run premium in it, it will be fine, but if you do put octane in, just put a little bit in it. because it could make your fuel too rich and foul out your spark plugs.
Why do i have spark knock in my 2004 Pontiac grand prix with v6 engine and can you use octane booster the car has 18000 miles?
Adding octane booster, or using higher octane fuel, will not hurt your car. Octane is actually a combustion inhibitor, not an accelerant. If your engine is truly knocking, it's because the fuel/air mixture, during the compression stroke, is igniting before the spark plug is expected to fire. (The fuel/air mixture, under compression, should not "explode" before your distributor sends the "Voltage" needed to make the spark plug fire. This should only happen at the very end of the compression stroke.) Adding higher octane fuel will prevent the fuel from igniting under compression, allowing the compression cycle to complete its phase to completion. Higher octane fuel also burns slower, so it may even smooth-out your idle. Either way, your car should be fine - Just make sure your plugs are gapped properly, and knocking is really the problem - The best bet is to just go up one octane level at the pump. If the problem goes away, stay with that grade fuel. If not, go up to premium - And check again. (If your vehicle is designed for 87 octane fuel and you need to burn 91 octane fuel to stop knocking, I'd seriously consider having a mechanic diagnoe the problem.)
What fuel gets best mpg?
All major brands of fuel are basically the same. Ethanol is one fuel that does not provide good milage. Ethanol significantly reduces your fuel mileage because alcohol contains less energy than gasoline. The EPA says you will get about 7 mpg less with E85 that with 100% gasoline. But with gasoline it is imperative you use the correct octane. Simply put, octane is a measure of gasoline's ability to resist detonation, which you hear as pinging and knocking in your engine. The higher the octane the more the fuel can be compressed without detonating before you want it to. Detonation, ping, knock, whatever you want to call it, occurs when the air/fuel mixture ignites before the spark plug fires. The mixture ignites from compression and not from the flame of the spark plug. In other words, the higher the octane the less likely it is to ignite prematurely. The only benefit to a high octane fuel is that it allows an engine to run at a higher temperature and with a higher compression ratio without pinging. Higher octane fuel does not provide more energy, more power, better mileage, more torque, burn cleaner, clean your engine, and is not better for the environment. If the engine is pinging when using the correct octane fuel, then it may be necessary to move to the next higher octane to prevent pinging, and damage to your engine, unless there is another problem. If you are using higher octane fuel for any of these reasons, STOP, you are throwing your money away. Also, never use a lower octane fuel than is recommended by the manufacture. If the manufacture recommends 89 octane then use 89. If they recommend 87 then use 87. The key is what was the engine designed to run at to achieve optimum performance and mileage? One exception is when you are towing a heavy load with a vehicle designed to run on 87 and you experience pinging. In that case it may become necessary to switch to 89 while towing. In conclusion, race car engines are designed to run on high octane fuels due to their high compression engines. You cannot make your engine a race engine just by upping the octane. Save your hard earned money, and use exactly the octane you need.
What is octane number of a fuel?
Many car engines run on gasoline. If the octane is low, the engine will knock. If it is high, the engine will not knock, which means that sometimes it will make a knocking sound as you drive along. It also might keep running when you turn off the key to the car. With high octane, the engine also starts easier. It is more expensive to make high octane fuel. Lower octane fuel gets better milage. There are two organic chemicals: isooctane and heptane. Isooctane is a good fuel for cars. It is rated at 100 octane. Heptane is a bad fuel for cars. It is rated at zero octane. When gasoline is made, they need to make a certain octane. They put the gasoline in a car engine. They then run the car with a mixture of isooctane and heptane. They find the mixture that matches the batch of gasoline. That is the octane rating of the new batch of gasoline.
How do you stop spark knock?
To stop spark knock , try a higher octane fuel. Make sure that the engine is timed properly and that the spark plug type isn't considered too "hot."
