engine cylinder weight and power

miqoooo

Can anyone tell me if engine cylinder weight lowers, does it make change in fuel consumption or the power of engine?

berkeman

Welcome to the PF.

Cylinder weight wouldn't have a direct effect on those quantities, I wouldn't think. What is the context of the question?

jack action

The power will be the same.

It would not change the fuel consumption per horsepower, but it will change your fuel consumption «per acceleration».

At steady state (like a car cruising at constant speed), engine weight is irrelevant (well, because my example is a car with some rolling resistance, «mostly insignificant» would be more accurate). But when the engine has to accelerate, the heavier the moving parts, the lower the acceleration. If you have to accelerate the engine itself (like in a car), the weight of the entire engine (including block, cylinder head, etc.) is also relevant and it will affect acceleration.

miqoooo

I don't understand,if the cylinder weight makes difference in fuel consumption, why don't the car producers make the cylinders from carbon?

jack action

Cost, reliability. If it was that easy to do, it would have been done a long time ago. But they're getting there:

http://www.agcoauto.com/content/news/p2_articleid/185
http://vincentciulla.suite101.com/gm...anifolds-a7344

Lsos

A more fundamental question is why they don't make the whole CAR out of carbon. The answer is that they DO...except these cars tend to cost $1,000,000.

It's an expensive material and process.