During the combustion stage, How important is it to have the entire gas heated at the same temperature? And how can you go about getting the best result? Also do the kinetic energy of a gas change instantly going from low kinetic energy to very rapid when you introduce extreme heat? Even though it's only applied for a millisecond. Does the gas need to make direct contact like it does when it gets enveloped with the heat to change kinetic energy and cause as much pressure as needed for a piston to be forced down?

  • 1
    Depends on the type of combustion if you are talking about gasoline engine it is very important to burn all the gas, as gasoline can go through the catalytic converter and damage it and/or foul the spark plugs while for diesel engine it is not uncommon to still have left over fuel from and a cycle
    – method
    Commented Nov 10, 2016 at 6:29
  • What do you mean by "entire gas heated"? Gasoline? Gas as in oxygen? Heated when? There's a dozen questions here. Maybe just some time reading is best for now, and come back when you have a clear idea of what you want to ask.
    – cory
    Commented Nov 10, 2016 at 15:39
  • Sorry I wasn't specific. I was in feed talking about gasoline engines.
    – LostPecti
    Commented Nov 11, 2016 at 5:44

1 Answer 1


As method 5 mentioned it is important for gas engines and not as important for diesels.

In a gas engine in a car you can foul spark plugs, catalytic converters, and create carbon deposits not to mention lower performance. In a diesel you will have carbon deposits and on ones with catalytic converters you can fowl them.

you can ensure more fuel burns by adding more spark plugs per cylinder, creating hotter sparks, atomizing the fuel better, heating up the fuel charge before it enters the cylinder, increasing the compression, and making sure your air fuel mix is perfect.

the kinetic energy is not instant it's a wave more or less and this is why spark happens way ahead of TDC at higher RPMs because by the time the piston passes TDC the pressure from the burn will have finally caught up.

The last question you had is a little confusing but I will try to answer what I think you are saying. what happens is the heat energy from the reactions of the fuel and air increase the molecule's energy and make it zip around faster and some percentage of all these now moving really fast molecules hit the top of the piston and when enough of them hit the top of the piston it moves down. if there are too few molecules they may not hit the piston as explained here the worlds smallest steam engine

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    Sorry again my answer was confusing. On the last question I meant do the gas heat up by convention? Or would it take to long to heat the gas that way in the time frame needed? If so do the gas particle have to heat another way other then convention and if so. What way and why?
    – LostPecti
    Commented Nov 11, 2016 at 5:47
  • I don't think convention is the correct word here. I am guessing english is not your first language so if you want write that comment in your language I can try to translate it using google translate or some other service. The only words there that would fit in relation to combustion is compression or combustion. this will also allow me to give you a more pointed answer. I think my last section (world's smallest steam engine) answers this but apparently not.
    – Cc Dd
    Commented Nov 14, 2016 at 4:59

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