Engine Capacity Vs Fuel Consumption

[sira]

Hi

I have heard from some of vehicle owners saying 1300 is more fuel consumption than 1000cc as well as 1500cc is better than 1300cc

Can anybody tell me is this logically correct or not

sira

Edited July 15, 2011 by sira

[The Don]

Hi

I have heard from some of vehicle owners saying 1300 is more fuel consumption than 1000cc as well as 1500cc is better than 1300cc

Can anybody tell me is this logically correct or not

sira

Research two concepts, power to weight ratio and torque.

Power to weight ratio is the amount of power a car engine produces vs its weight, and what we're aiming for is a balance (not too high not too low) if economy is our main focus.

Torque is the amount of pulling power an engine transfers to the wheels.

Also remember vehicles tend to burn more fuel (economy decrease) when it's consistently operating in higher revs. This is because the power output of an engine peaks at a certain rpm and then goes down and it's not a straight line to begin with (not completely relative, more a curve).

So to put all of the above, what we want is a vehicle whose engine is nicely balanced for the weight of the car. If the car is too heavy for the engine, you will spend a lot of time revving the car to gain momentum and in the process lose fuel economy.

The reason why I mentioned torque is that in Diesel vehicles the maximum torque is delivered at much lower revs, and tends to be higher than petrol cars so you might have less power figure (expressed in BHP) and the power to weight ratio might be low, but the engine might deliver more torque and the car might be more economical than an equivalent petrol.

So in short, what you have heard is possible.

[Schiffer]

in simple, for a car with a 1300CC engine needs more pulling power to drag the weight of the car

the more force it uses, the more fuel it burns

[CyRaX]

Normally we would say yes a higher

capacity car burns more fuel. that sounds logical.But do consider the driving

styles which would vary. one thing about smaller capacity cars is that, the engines are

actually working much harder, so in a sense, they would actually burn more petrol to

produce the same amount of bhp as a larger capacity engine. but then, cars with larger

capacity engines tend to be bigger, and heavier, henceforth, that is why they may have to burn more fuel, to get more power to move that extra mass.

[heavyD]

The number of gears matter too. A six speed box will return better figures than a four speed box for example.

Edited July 16, 2011 by Big_D

[kelum_wj]

It also depends on the power output. A 1500cc engine of one make would produce 130 bhp while the other would produce 100 bhp. And also the RPM which the maximum power is achieved. The engines which produces more power at lower rev bands would be more fuel efficient in city driving

[virensti]

basically, don't believe the sri lankan mindset which is "the bigger the engine, the more fuel consumption" as The Don mentioned, power to weight is the number 1 factor in fuel economy...

in other words,

just cause the car has a 1.0l engine (i.e vitz) it doesn't mean that it does better on fuel than a 1.5l engined vehicle.(i.e swift)in this case, the swift will actually do better on fuel than the vitz..