Difference Between Octane 92 And 95 Gasoline Fuel

The main type of fuel for refueling modern cars is gasoline. It is a product of oil distillation, one of several fractions. The current state standard divides it into several groups (brands). The most famous are AI-92 and AI-95. Let’s discuss the difference between octane 92 and 95 Gasoline Fuel.

difference between octane 92 and 95 Gasoline Fuel

Gasoline AI-92 (octane 92) Fuel

Petroleum products of this brand are classified as regular. Approved by the standards of European countries. High octane fuel. The main application was found in cars equipped with carburetor internal combustion engines. It is also used in machines with injection fuel supply systems, in which the engine operates with air at normal atmospheric pressure (atmospheric).

But this type of gasoline in Europe is gradually disappearing from gas stations. It is no longer produced. They were replaced by high-octane types (AI95, AI98), which have greater resistance to detonation. Most of the countries, the A 92 remains a popular type of automotive fuel. It is freely available at all gas stations in the country.

The abbreviation AI 92 has its own explanation. So the letters “A” mean that the fuel is automotive, the octane number of which (92) is determined by the study (“I”).

Interesting: Most believe that the higher the octane number, the better the fuel. However, it is not. When choosing a brand for refueling, you should focus solely on the recommendations that the manufacturer gives to a particular car.

The main characteristics of AI-92 include the content of lead – no more than 0.0135 g / dm3), resin – less than 5 mg / dm3), with a density of 725 to 780 kg / m3 and a boiling point of 33 to 205 degrees C. The flash point of gasoline is the same as for other brands – about 40 degrees C.

Gasoline AI-95 (octane 95) Fuel

AI-95 gasoline is a representative of the Premium motor gasoline group. Currently, it is the main type of fuel for cars. It is gradually popular and in demand, due to the fact that the majority of manufacturers of modern cars include the use of gasoline with an octane rating of 95 and higher in their characteristics.

It has improved features. In its production, aromatic additives, natural gasoline, and fractions obtained from petroleum distillates through their high-temperature processing are used.

AI-95 has high resistance to detonation, as indicated by an octane rating of 95. It is almost completely free of the presence of lead, which has become one of the main reasons for environmentalists in the fight against the more environmentally harmful AI-92.

The state standard for AI-95 imposes the following requirements: lead not more than 0.01 g/dm3; the presence of resins up to 5 mg/100 cm3; the presence of hydrogen sulfide up to 0.5% of the total mass; density from 725 to 780 kg/m3; boiling point from 33 to 205 degrees C.

difference between octane 92 and 95 Gasoline Fuel

The main difference between the brands of automotive fuel under consideration is resistance to detonation. The higher the octane number, the worse the gasoline burns.

The second important point in answering the question of how 92 gasoline differs from 95 gasoline is that the second one does not contain lead (tetraethyl lead) and contains more additives, the main task of which is to create conditions for greater efficiency and fuel combustion rate. This results in lower fuel consumption and a greater return on the vehicle’s transmission.

Modern engines have a high degree of compression of the air-fuel mixture. Therefore, the fuel for them must be resistant to detonation, have a higher octane number.

Gasoline manufacturing technology

The creation of gasoline provides for mandatory steps and stages:

  1. Oil distillation (simple method, cracking or reforming);
  2. The division into factions;
  3. Separation of finished gasoline.

A simple oil distillation method

It has been widely used since the appearance of the first cars. It consists of a number of sequences in the processing of crude oil: the creation in a column, using heating and a coil, of heated decomposition products; raising oil vapors by passing them through the liquid solution; a collection of condensate in a special container; selection, with the reverse flow into the column, of light fractions.


One of the most used methods for producing gasoline with a high octane number (AI-92, AI-95). It consists of the decomposition of oil into fractions by high-temperature exposure to obtain new substances with a lower molecular weight.

When oil is brought to a boil, carbon bonds are broken. The output is a series of derivatives:

  • volatile and liquid gases;
  • initial fractions of fuels and lubricants (fuel, oils, lubricants);
  • residual heavy products (fuel oil, bitumen).

Cracking is impossible without the use of catalysts.


The process of obtaining light oil products by processing linear hydrocarbons. The molecular hydrocarbon is not split but converted into fractions with a high octane number.

Two types of reforming are currently used in refineries – thermal and catalytic treatment. The second process is similar to cracking, but it is not the oil that is heated, but the catalysts. This is a very costly production, but it allows you to create high-quality automotive fuel.

The thermal reforming method is the most common. Essentially, this is a type of cracking process that converts low-octane substrates into high-octane gasoline. Passes at temperatures from 510 to 565 degrees C, and high pressure, from 18 to 70 atmospheres.

Differences in the production of 92 and 95 gasoline

There are no significant differences in the production of the brands under consideration. Undivided automotive fuel is obtained in the process of decomposition into fractions during the distillation of oil, at the 2nd stage. Further, fine purification takes place and gasoline, intended to become AI-95, is purified from lead and receives a portion of additives to increase the octane number.

Methods and uses of additives in octane 92 and 95 gasoline

Additives are chemicals used to improve fuel quality. They increase the life of the motor, increase power, and reduce the level of toxic gases.

Additives are divided into 2 types:

  1. Used for the production of gasoline.
  2. Local, designed for consumers (washing, anti-smoke, etc.).

The former are purchased by refineries and enterprises that produce fuel on an industrial scale.

The latter are intended for consumers, maintenance stations, and auto enterprises. There are more than 20 types on the market. Main: depressor; anti-smoke; detergents; antiwear; restoring; antioxidant.

The main method of their use is mixing. It consists in the fact that a reagent is introduced into the fuel, which has a high resistance to ignition. Usually, the chemical is monomethyl aniline, with an octane rating of more than 250 units.

An earlier popular gasoline additive was tetraethyl lead, the addition of which resulted in full power output from the fuel. However, lead deposits formed in the engine cylinders are harmful to the human respiratory system. Now tetraethyl lead as an additive to gasoline is prohibited, including because it contributes to the rapid wear of engines.

Alcohols, esters are the simplest options for increasing the octane number. But the content of such additives, according to established standards, should not exceed 15%.

can you mix 92 and 95 gasoline Fuel?

It can be assumed that by mixing 92 and 95 gasoline in equal proportions, fuel with an average octane number is obtained. And the cost of such a composition (mixture) will also be average. This is attractive in the face of a constant increase in fuel prices.

And if it is possible to obtain an average cost by mixing these brands, then it will not work to create an intermediate octane number.

AI-92 has a higher density than AI-95. And if you pour these brands of gasoline into the tank of a car, they will not mix. Gasoline denser will concentrate at the bottom of the tank, and lighter in its upper part.

Thus, it turns out that for some time the car will produce the 92nd, and then it will switch to the 95th. And if the compression ratio of the internal combustion engine is more than 9, then driving on the AI-92 will lead to detonation in the engine cylinders, significantly reducing its service life.

octane 92 vs 95 Gasoline Fuel: what octane fuel should i use?

Experts disagree on which gasoline is best for a car.

Some people constantly pour AI-92 into the tank, while the manufacturer advises refueling with the 95th. And this decision is explained by a small number of additives. Indeed, there are cases when AI-95 caused the reddening of candles, soot on them, and other problems.

However, before experimenting with fuel, it is still recommended to familiarize yourself with the requirements of manufacturers for gasoline. And if the use of only AI-95 is structurally laid down, then fuel with a lower octane number should not be poured into the car tank.

Moreover, if the use of the 92nd is provided, then there will be no unpleasant consequences for the motor from the 95th.

Leave a Comment