Leovitara,no, tal como te dice Juan Manuel, la nafta común te puede fallar.
FIjate que en números, una relación de compresión de 8,4:1 ya necesita nafta de 90 octanos para andar normalmente bien, con el motor en condiciones normales.
Si tu Vitara tiene una relación de compresión de 8,9:1 necesitarás una nafta mejor que los 90 octanos. La nafta comun creo que tiene solo 85 y no alcanza. Con la super de 95 octanos andarás bien, y no necesitás derrochar dinero en una de 97 u 98 octanos que tu motor no podrá aprovechar.
Con 8,9:1 de relacion de compresión necesitarías, teóricamente una nafta de Aprox. 92 ó 93 octanos, y no hay en el mercado. Estás muy lejos de los 85 octanos de la comun, y la super de 95 te sobra un poquito. Sin dudas, yo podría la super de 95.
Saludos,
duda respecto a octanaje del combustible
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D MarutÃstico
- Nuevo Suzukero !
- Mensajes: 16
- Registrado: 25 Sep 2004 20:49
- Ubicación: Capital Federal - Palermo
Octanos
Diego A
Grand Vitara 2.0 Nafta Verde Naturaleza
Grand Vitara 2.0 Nafta Verde Naturaleza
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NachoJimny
- Suzukero Fanático !!!
- Mensajes: 1734
- Registrado: 22 Sep 2004 13:39
- Ubicación: Bariloche
guelvo a insistir... estamos de acuerdo en lo que dicen pero hay algo mas.. que aun no lo encuentro... y la verdad no desarme la biblioteca buscando esas pruebas... pero habia una pequeña diferencia a favor de las naftas premium. y no era sugention ( A Papa-mono Psicologo con bananas-sugestivas jaja?) no . contra mi voluntad me ddaba cuenta que se comportaba levemente diferente...
El dia que encuentre la pruebas...
me acuerdo que habia una foto de un mozo con dos vasos llenos de dos liquidos diferentes...
El dia que encuentre la pruebas...
me acuerdo que habia una foto de un mozo con dos vasos llenos de dos liquidos diferentes...
Que como anda la Cherokee? es un Toro en celo! Cherokee 4.0 Red Bull
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NachoJimny
- Suzukero Fanático !!!
- Mensajes: 1734
- Registrado: 22 Sep 2004 13:39
- Ubicación: Bariloche
Toma mate pero banca el ingles... abajo habla de los aditivos de los combustibles...
If you've read How Car Engines Work, you know that almost all cars use four-stroke gasoline engines. One of the strokes is the compression stroke, where the engine compresses a cylinder-full of air and gas into a much smaller volume before igniting it with a spark plug. The amount of compression is called the compression ratio of the engine. A typical engine might have a compression ratio of 8-to-1. (See How Car Engines Work for details.)
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, methane, propane and butane are all hydrocarbons. Methane has a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.
It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
Gasoline additives
During WWI, it was discovered that you can add a chemical called tetraethyl lead to gasoline and significantly improve its octane rating. Cheaper grades of gasoline could be made usable by adding this chemical. This led to the widespread use of "ethyl" or "leaded" gasoline. Unfortunately, the side effects of adding lead to gasoline are:
Lead clogs a catalytic converter and renders it inoperable within minutes.
The Earth became covered in a thin layer of lead, and lead is toxic to many living things (including humans).
When lead was banned, gasoline got more expensive because refineries could not boost the octane ratings of cheaper grades any more. Airplanes are still allowed to use leaded gasoline, and octane ratings of 115 are commonly used in super-high-performance piston airplane engines (jet engines burn kerosene, by the way).
Another common additive is MTBE. MTBE is the acronym for methyl tertiary butyl ether, a fairly simple molecule that is created from methanol. Click here to see MTBE's chemical structure.
MTBE gets added to gasoline for two reasons:
It boosts octane (see this Question of the Day for a discussion of octane).
It is an oxygenate, meaning that it adds oxygen to the reaction when it burns (see this Question of the Day for a discussion of oxidizers). Ideally, an oxygenate reduces the amount of unburned hydrocarbons and carbon monoxide in the exhaust.
MTBE started getting added to gasoline in a big way after the Clean Air Act of 1990 went into effect. Gasoline can contain as much as 10 percent to 15 percent MTBE.
The main problem with MTBE is that it is thought to be carcinogenic and it mixes easily with water. If gasoline containing MTBE leaks from an underground tank at a gas station, it can get into groundwater and contaminate wells. Of course, MTBE isn't the only thing getting into the groundwater when a tank leaks -- so is gasoline and a host of other gasoline additives.
According to this page at the EPA:
Although there is no established drinking-water regulation, USEPA has issued a drinking-water advisory of 20 to 40 micrograms per liter (µg/L) on the basis of taste and odor thresholds. This advisory concentration is intended to provide a large margin of safety for noncancer effects and is in the range of margins typically provided for potential carcinogenic effects.
The most likely thing to replace MTBE in gasoline is ethanol -- normal alcohol. It is somewhat more expensive than MTBE, but it is not a cancer threat.
If you've read How Car Engines Work, you know that almost all cars use four-stroke gasoline engines. One of the strokes is the compression stroke, where the engine compresses a cylinder-full of air and gas into a much smaller volume before igniting it with a spark plug. The amount of compression is called the compression ratio of the engine. A typical engine might have a compression ratio of 8-to-1. (See How Car Engines Work for details.)
The octane rating of gasoline tells you how much the fuel can be compressed before it spontaneously ignites. When gas ignites by compression rather than because of the spark from the spark plug, it causes knocking in the engine. Knocking can damage an engine, so it is not something you want to have happening. Lower-octane gas (like "regular" 87-octane gasoline) can handle the least amount of compression before igniting.
The compression ratio of your engine determines the octane rating of the gas you must use in the car. One way to increase the horsepower of an engine of a given displacement is to increase its compression ratio. So a "high-performance engine" has a higher compression ratio and requires higher-octane fuel. The advantage of a high compression ratio is that it gives your engine a higher horsepower rating for a given engine weight -- that is what makes the engine "high performance." The disadvantage is that the gasoline for your engine costs more.
The name "octane" comes from the following fact: When you take crude oil and "crack" it in a refinery, you end up getting hydrocarbon chains of different lengths. These different chain lengths can then be separated from each other and blended to form different fuels. For example, methane, propane and butane are all hydrocarbons. Methane has a single carbon atom. Propane has three carbon atoms chained together. Butane has four carbon atoms chained together. Pentane has five, hexane has six, heptane has seven and octane has eight carbons chained together.
It turns out that heptane handles compression very poorly. Compress it just a little and it ignites spontaneously. Octane handles compression very well -- you can compress it a lot and nothing happens. Eighty-seven-octane gasoline is gasoline that contains 87-percent octane and 13-percent heptane (or some other combination of fuels that has the same performance of the 87/13 combination of octane/heptane). It spontaneously ignites at a given compression level, and can only be used in engines that do not exceed that compression ratio.
Gasoline additives
During WWI, it was discovered that you can add a chemical called tetraethyl lead to gasoline and significantly improve its octane rating. Cheaper grades of gasoline could be made usable by adding this chemical. This led to the widespread use of "ethyl" or "leaded" gasoline. Unfortunately, the side effects of adding lead to gasoline are:
Lead clogs a catalytic converter and renders it inoperable within minutes.
The Earth became covered in a thin layer of lead, and lead is toxic to many living things (including humans).
When lead was banned, gasoline got more expensive because refineries could not boost the octane ratings of cheaper grades any more. Airplanes are still allowed to use leaded gasoline, and octane ratings of 115 are commonly used in super-high-performance piston airplane engines (jet engines burn kerosene, by the way).
Another common additive is MTBE. MTBE is the acronym for methyl tertiary butyl ether, a fairly simple molecule that is created from methanol. Click here to see MTBE's chemical structure.
MTBE gets added to gasoline for two reasons:
It boosts octane (see this Question of the Day for a discussion of octane).
It is an oxygenate, meaning that it adds oxygen to the reaction when it burns (see this Question of the Day for a discussion of oxidizers). Ideally, an oxygenate reduces the amount of unburned hydrocarbons and carbon monoxide in the exhaust.
MTBE started getting added to gasoline in a big way after the Clean Air Act of 1990 went into effect. Gasoline can contain as much as 10 percent to 15 percent MTBE.
The main problem with MTBE is that it is thought to be carcinogenic and it mixes easily with water. If gasoline containing MTBE leaks from an underground tank at a gas station, it can get into groundwater and contaminate wells. Of course, MTBE isn't the only thing getting into the groundwater when a tank leaks -- so is gasoline and a host of other gasoline additives.
According to this page at the EPA:
Although there is no established drinking-water regulation, USEPA has issued a drinking-water advisory of 20 to 40 micrograms per liter (µg/L) on the basis of taste and odor thresholds. This advisory concentration is intended to provide a large margin of safety for noncancer effects and is in the range of margins typically provided for potential carcinogenic effects.
The most likely thing to replace MTBE in gasoline is ethanol -- normal alcohol. It is somewhat more expensive than MTBE, but it is not a cancer threat.
Que como anda la Cherokee? es un Toro en celo! Cherokee 4.0 Red Bull
