Myths and facts about octane booster and other gasoline additives
High-octane … mm, taste the word. It breathes racing and performance. And from the racing business also come the gasoline additives. The question is, do you and I as motor-interested individuals in ordinary cars on public roads have any benefit from this?
A gasoline-powered car does not need to run on higher octane than it can handle.
Higher octane numbers mean that gasoline has more resistance to self-ignition. That is, it can withstand higher compression. And with higher compression, you get more power out of the engine.
But if you now have an engine that can handle 95 octane (which today is the lowest we have in Sweden) then you have no positive effect of refueling 98 octane.
Why?
1) higher octane number causes gasoline to burn more slowly - explosion will not be as powerful
2) higher octane number has lower energy content
3) higher octane number has higher liter price
However, if you have an engine that can adjust , such as the Volkswagen W8 ( here ) and that can accommodate 98 octane, mainly through a changed ignition point, but which can also be run on 95 octane, then the engine develops more power fueled with 98 octane .
Engines built for 98 octane without the possibility of government, like Volkswagen's and Audi's FSI engines without turbo, in the 00s, for example Audi A2 1.6 FSI and VW 2.0 FSI in many models, these cars must get their 98 octane, for they get the lower octane number, they will "nail" (ie self-ignite before the explosion is expected to come) with the risk of damage to pistons and valves mainly.
So who then needs octane- boosting additives, so-called octane boosters ?
The answer is
-the one that has a particularly high compression engine, ie a hard-trimmed special building, and
-the one that travels in countries with poor gasoline and low octane, with a car that requires, for example, 95 octane.
Best octane booster works better the lower the number of octane it is in the gasoline it should "boost" and thus the US is a much more grateful market than Western Europe for octane booster - in the US regular gasoline is 91 octane , while in Western Europe it is known as 95 octane.
Thus, it is much easier (goes for less octane booster) to raise from 91 to 95 octane than to raise from 95 to 98. And raising 98 octane is hardly possible.
Octane boosters aim to either dilute the gasoline with something that has higher octane numbers, such as toluene, or to stabilize the gasoline so that it does not ignite as easily.
The admixture of toluene may need to be as high as 30%, but because toluene burns slowly, a lot of unburned fuel will go out with the exhaust gases. Waste of fuel and will definitely give too high HC at Bilprovningen.