Earth, Air, Fire, and Water: The Fifth Element is found within a combustion chamber.
For, petrol comes out of the earth, and it is fire-water. Do you have a carburettor or injectors?
Which turns you on more: fuel being atomized by the vacuum that the motor itself creates, or fuel being atomized by a separate atomizer?
There is something poetic about a carburettor, but for efficiency. And if we make efficiency a second order concern, we join hands with those who talk about the good old days of American motoring, when fuel was cheap, and engines of ridiculous dimensions: days which have been written and sung about, when Americans of a weekend, got into their cars and played with their wind socks.
The Sixth Element is Carbon.
The moral of the story is never ask a mathematician to contemplate chemistry.