Don't Put Sugar in Your Gas Tank, Sugar

Question: If you put sugar in the petrol tank does if give you a boost?
Would you put gasoline in your coffee? Same difference. Sugar is for people, gasoline is for cars. So no, don't put sugar in your gas tank (or gasoline in your coffee).

Ok, I'll explain this a bit. Putting sugar in your gas tank will, not might, will cause problems. The least damage it will do is plug the fuel filter and cause the engine not to work. The most it will do is destroy the engine. How much damage happens depends on the age of the car and the winds of fate. Todays cars are designed to run on very refined, low particulate gasoline and as such have filters in them that strain tiny amounts (Usually 2 microns). Older cars have a mesh screen, or no filter at all in them because they were designed to run on higher particulate gasoline (remember leaded gasoline?). So a new car with sugar in the fuel would get a clogged fuel filter. Older cars that would let the sugar continue into the engine are a different story.

Back story #1- In any gasoline engine a mist or spray of gasoline is atomized and combined with air to produce an extremely volatile and explosive mix which is what the engine uses to produce power. In a standard 4-stroke engine the fuel is compressed by the pistons and ignited by spark plugs producing a controlled explosion which produces power. If the air/fuel mix ignites too early the result is knocking, pinging and in some cases detonation. If it ignites too late the result is lots of smoke, excessive engine deposits and in some cases, hydro-locking the engine. So it is a delicate balance that the engine has to use to get the most power out of each explosion of each cylinder. Carburetors and distributors controlled this balance on older cars, engine control modules control it on new cars and these controls can adjust the engine a little bit to make up for irregularities in gasoline quality and octane rating, ambient temperature, etc.

Adding sugar to the fuel mix causes gasoline, a light evaporative fuel, to become sticky, thick and, worst of all, raises the ignition point massively. So you have an engine that produces anywhere between 118psi (8:1 compression ratio, 350cid) and 185psi (12:1 compression ratio, 350 cid) trying to compress a fluid (instead of a gas) and ignite it.

Back story #2- Hydraulics uses a liquid to move a load through pressure generated by a pump and a prime mover. The only reason why hydraulics works (and is capable of some amazing force. Like a hydraulic, hand operated jack being able to lift 4 tons. Or the 100 ton press I have in my shop that I use to squish pennies) is because force required to move the load is less than the force required to compress the hydraulic fluid, destabilize the frame of the piston or stop the pump. Basically, it is generally agreed than you cannot compress a liquid. (You can but only under great force and only a tiny bit)

So the sugar/gas mix that is in your engine has transformed a pneumatic (compressed air) system into a hydraulic (compressed liquids) system. Engine blocks are exceptional at many things but containing the 1/2 ton or so of pressure created when trying to compress a liquid isn't one of them. One of four things will happen: The side of the engine will blow out, the crank will snap, the cylinder head will blow off, or the valves will bend and seize. Basically turning the engine into a really heavy paper weight.

So don't put sugar in your gas.


The Motachanic

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