I'm bored so here goes...............
Aviation fuel is either 100LL or 110LL octane rating. 130 is not avaible. The aviation fuel is a bit odd it has stabilisers
Avgas is formulated for use in aircraft, the chemicals are quite different that go into making it, the thing with Avgas is that it is designed to produce a constant octane rating through a range of altitude as its main use is in light aircraft with piston engines. It properties are quite different from pump fuel.
As with any feul there is always a trade off.
Antiknock Additive. Usefull for high compression engines.
The most important avgas additive is tetraethyl lead. It is added as part of a mixture that also contains ethylene dibromide and dye. Ethylene dibromide acts as a scavenger for lead. When avgas is burned in an engine, the lead in tetraethyl lead is converted to lead oxide. Without a scavenger, lead oxide deposits would quickly collect on the valves and spark plugs. If the deposits become thick enough, they can damage the engine. Ethylene dibromide reacts with the lead oxide as it forms and converts it to a mixture of lead bromide and lead oxybromides. Because these compounds are volatile, they are exhausted from the engine along with the rest of the combustion products. Just enough ethylene dibromide is added to react with all of the lead. However, because the reaction does not quite go to completion, a small amount of lead oxide deposit is found in the cylinders of engines!
However, be warned there are no corosive inhibiters in Avgas that is comercialy available, only for Militay application.
Engine and fuel are interdependent components of a single system. Each engine is designed and certified for fuel with a specific minimum antiknock performance. Using a fuel with a lower antiknock performance will produce less knock-limited power and possibly damage the engine under severe knock conditions. Use of a fuel with a higher antiknock performance is not harmful, but provides no benefit.
The energy content of avgas can be measured; it is the heat released (also called the heat of combustion) when a known quantity of fuel is burned under specific conditions. The amount of heat released depends on whether the water formed during combustion remains as a vapor or is condensed to a liquid. If the water is condensed to the liquid phase, giving up its heat of vaporization in the process, the energy released is called the gross energy content. The net energy content is lower because the water remains in its gaseous phase (water vapor). Since engines exhaust water as vapor, net energy content is the appropriate value for comparing fuels.
This will give more heat as there is more heat per quantity of fuel. The feul vaporisation characteristic are also very different, this gives way to different combustion patterns inside the cylinder.
Anyway there is a cheap, easy and harmless way to increase octane ratings in fuel, simple, just add an aromatic compound. These can easily add 10 to 15 octane points to your fuel.
I'm not endorsing anythign here and not suggesting anyone does this and i'm not responsible if you do - especially if your engine goes pop!
Just some basic thoughts............ 8)
