Engines of power?

This is a note to my notebook

I had a strange thought the other day while watching a programme about rocket powered cars. I think the programme was on one of the satellite channels that we have here at home. Now my thought was not about the rocket car itself. It was about cars in general and at some stage, I don’t know how long it took but I got to think about the engines in cars and then on to the internal combustion engine (see that jump in thoughts did you?)

Now my thoughts were along the lines of the petrol engine, which has now been around for what 90 odd years? just how much of it has been improved?

I do know that parts are now made to better tolerances and that the weight of engines has come down as new materials have been found and used in the manufacture of engines. I also know that the oils used in the engines are much lighter and do a better job of making the metal parts not stick together (which is apparently a good thing).

I believe that the spark plugs and the way the fuel is put into the engine has also been improved over the years, the valves that control the way air and the exhaust are controlled have been made lighter and better, meaning I think that they will last longer.

But as this was my question to myself, is the engine of today any more efficient than say one of 10, 20 or 30 years ago? I don’t have an answer to this question, going onto the internet and giving Google a good going over also failed to give my any real answers, perhaps no one has asked this question? I don’t know. I do know that some one could have a great engineering thesis on it.

One other thought that I did have was this has the design of the pistons changed much in the 90 years that have gone by; it’s true that the material that is used to make the pistons has changed generally to lighter materials. Has the shape changed? Have the piston rings changed in shape and the material that they are made of?

I don’t know the answers to these questions, now the clever people out there might have the answer to these silly questions, what I want to know is there a way to improve the internal combustion engine?

Could you for instance change the shape of the piston? The shape of the piston rings? The shape of the oil sump? Or change what material they are made from?

Would any of these changes make any difference to how efficient the engine is?

I know that a lot of the energy in petrol ends up as heat and not motive power, is there a way of making sure that some of that heat is not produced and is put into moving the car?