In fact, until the 80s, gasoline was illegal for us until recently. Back in 2008, with the introduction of the Technical Regulations for Fuels, they explained to us popularly: they are bad, environmentally dirty, and foreign cars of officials and deputies are in no way suitable. Therefore, they were not even included in environmental class 2, the lowest in the Regulation.
The entry into force of this sophisticated document has been repeatedly delayed. Finally, in the fall of 2011, when only class 4 gasoline was to be sold (according to the first version of the Regulation) throughout Russia, it turned out that most refineries had not even reached class 3 (such fuel was allowed to be produced before the end of 2009)! At the pace, the next amendments were adopted, which … canceled all restrictions on the octane number. Now you can, without looking back at the deadlines, produce any gasoline, at least 72nd, at least 110th, if only all other requirements for environmental friendliness of fuel have been met.
However, the process has begun: since 2008, oil companies have been curtailing the production of 80th gasoline. Today, although he is "in law", he is in terrible shortage! And since the largest refineries ceased to produce it at all, this brand is being transported from old plants that did not have time to wake up with the introduction of the Regulations, or from semi-artisanal mini-refineries, where they receive cheap low-quality surrogates, distilling gas condensate. As a result, the refueling of the 80th has now become difficult, and relatively expensive, and unpredictable in its consequences!
How to feed the old dinosaurs? There are ZILs with “Muscovites”, and old motorcycles, and outboard motors … Could it be bad for them? Check it out.
OLD SCARES AND NEW REALITIES
Smart mechanics, having read books, say that the use of high-octane gasoline in old engines is fraught with increased consumption, loss of power, a sharp increase in toxicity. And the worst thing is that the valves and pistons will burn! And all because high-octane gasoline burns worse, slower compared to low-octane. But is it?
The authors long looked at the stand with the old Volgovskiy ZMZ-4021. Our task extended his life: let him serve people for the last time! Having chosen gas stations with a reputable brand, so as not to run into a body weight on the move, we bought a canister of the 80th, 92nd and 95th. They cost respectively 25 rubles. 80 kopecks., 26 rubles. 50 kopecks and 28 rubles. 20 kopecks per liter.
Then we went through the usual test cycle, successively changing varieties. We measured fuel consumption, power, and exhaust gas toxicity at ten points characteristic of a universal operation cycle. To assess the temperature change of the exhaust valves (and, indirectly, of the piston group), we put a thermocouple on the outlet.
To begin with, no adjustments were made to the ignition system. The engine started and worked perfectly fine. The measurement results showed that on the 80th gasoline with standard adjustments, the power was a little more and the motor ate less gasoline - by 3-5%. And the higher the octane number, the greater the difference. But with toxicity the opposite is true! On the 95th gasoline, the environmental performance of the engine was better than on the 80th, but not much - by 10-12% (this only slightly goes beyond the measurement error). Moreover, the greatest effect is noticeable in reducing the yield of nitrogen oxides.
But what about the worst - are the valves and pistons intact? Definitely - yes! The temperature of the exhaust gases, if it depended on the octane number of gasolines, is very weak. All the difference fit into 15–20 ºC!
In the end, we decided: it’s stupid to overpay for more expensive gasoline, without using its advantages. Moved the ignition timing 5 degrees ahead - on old carburetor cars it’s easy. The result was not long in coming: power losses as it had happened, profitability was 2-3% better than when working on the 80th with regular engine adjustment.
So, the inversion of the intestines is canceled!
LOSE - FIND
The first plus is that the transition from the 80th to high-octane fuels does not threaten the motor with anything bad. The valves will not burn out, the pistons will remain intact. But the books are not to blame: they are simply written a very long time ago! In the era of leaded gasolines, the addition of lead to fuel seriously slowed down its rate of combustion. Yes, and iron in the form of ferrocene so beloved by the oil industry workers, too. But now the Regulation strictly prohibits the presence of any metals in the fuel (at least thanks for that!). And modern technologies for increasing the octane number, based on the optimization of the hydrocarbon composition of fuels and partly on the use of oxygen-containing high-octane components, on the contrary, improve fuel combustion. This is exactly what we saw in the experiment: the temperature of the exhaust gases when working on high-octane gasolines did not increase (its increase serves as the first sign of prolonged burning of fuel).
Why did we let a little, but lost in power, until we changed the adjustment of the motor? The fact is that high-octane gasolines have lower calorific value. That is, when burning one kilogram of fuel, they emit less heat than the same 80th. But this does not mean that they are worse: calorific value is only one of the parameters, by the way, not included in the regulation. But the reserve of detonation resistance allows you to remove higher power from them!
The second plus is the improvement of environmental parameters. Of course, the transfer from the 80th to the 95th old engine can not be converted to Euro-4, but it will become a little less spoil the air. This is where the misunderstanding of officials affects! It’s not low-octane gasoline that is dangerous for the environment - the content of harmful substances in the exhaust when working on the 80th is not much different from that achieved on high-octane fuel! A toxicity that exceeds all reasonable requirements is dangerous for the engine itself, which consumes 80th gasoline and was designed in the years of our grandfathers' youth. Reduction of environmental damage is achieved not by gasoline, but by the modern organization of the work process and effective toxicity suppression systems.
The third plus is that even an old engine running on modern fuel will be less polluted. It will affect both the quality of combustion and the presence of detergents in gasoline. And is it important! True, stratifications in life-beaten engines are probably not from fuel, but from the combustion of oil, but still …
The fourth plus is that you don’t have to spend time looking for the 80th, which has become scarce. (For example, we found it only at the fourth gas station.)
The fifth plus is less likely to run into the hell on what. The reasons - see above … Normal refineries of low-octane fuels are almost never produced, and the quality of gasoline produced at mini-refineries is usually lower than the lowest baseboard.
There is only one minus: refueling will cost more. But now it’s not much: taking advantage of the deficit of the 80th, oil prices quickly pulled it up to the prices of the 92nd.