Does Engine Size (in CC) of car Matters for Fuel Economy?


Does Engine size of car matters for Fuel Economy for same driving style?


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Nice subject! Engine Size is something we should define very carefully. First look at the parameters that affects an engine's size. The two dimensions of the piston chamber, bore and stroke determine an engine's actual size.Bore: Is the diameter of the piston chamber.
Stroke: Is the distance the piston travels within the piston chamber.

The Bore & Stroke measurements combined with No of cylinders will give the displacementof the engine which we normally call by 1.2 litter, 2 litter etc. Simply said, an engine's displacement is a measure of how much of that air/fuel mixture it moves in one cycle. When we can push more air through the engine, we will get more power (remember Turbocharger here!)

However, when we increase the air flow, it takes fuel as well because Fuel and air is always mixed together. A bigger engine pushes more fuel through it as well as air, raising fuel consumption. This is why larger, more powerful cars generally have lower FE. Smaller engines can push more air too, increasing the power and decreasing the FE. Gear ratios can be adjusted to get good FE for bigger engines and even may get better FE than a small engine, however at certain speeds. In general, the larger and more powerful an engine, the more fuel it uses.

PS: Also note the points posted above
 
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I voted for the option 'Yes', as I think, other things like technology, driving style/skill, weight, etc., being equal, the cubic capacity of the engine does matter, when it comes to the fuel efficiency.
 

AMG

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@ Knight
You are wrong.
Imagine a big engine of aluminium and imagine a relatively smaller engine of iron.
Which will be heavier?
 
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In my Post No 15, by ' engine size ' i meant the ' CC ' (Cubic capacity of the engine).


Gear ratios can be adjusted to get good FE for bigger engines and even may get better FE than a small engine, however at certain speeds.
Nice Point - Had forgot how important the ratios are.

7) Gear Box (Gear Ratios)

I'm getting confused.
Are we talking about physical size of the engine or size in terms of Cubic Capacity here?
As already said by Knight, Yes we are talking here in terms of CC (Cubic Capacity).Higher the CC bigger is the engine size and its weight.

@ Knight
You are wrong.
Imagine a big engine of aluminium and imagine a relatively smaller engine of iron.
Which will be heavier?
After so many posts is this what you understood ? [evil]

BTW no one makes iron engines.[cheers]
 
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No buddy, unless the engine is termed as 'All aluminum' engine, cast iron is definitely being used in that engine.

e.g: The famous JTD engines from FIAT
Not my mistake [lol] he said IRON and not CAST IRON.

Anyways the engine material is decided keeping in mind at what level the engine has to perform rather than the fuel efficiency.

So there is no way small cars coming with all aluminum engines.
 
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Thread Starter #24
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Moderators can you please modify the thread name from "Does Engine size of carmatters for Fuel Economy ?" to "Does Engine size of car (in CC) matters for Fuel Economy ?" to avoid any confusion and fight.
 
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Moderators can you please modify the thread name from "Does Engine size of carmatters for Fuel Economy ?" to "Does Engine size of car (in CC) matters for Fuel Economy ?" to avoid any confusion and fight.
I don't think its necessary.Oh come on .. we don't go and measure our engines sizes with measuring tapes to talk about them in that way.[;)]

When we talk about engine size its always about the CC (Cubic Capacity)
 
Thread Starter #29
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Thread Renamed. Let us keep the discussions positive and healthy.

Drive Safe,
350Z
[thumbsup] Thanks ! Was planning to leave office some time back. Suddenly stopped seeing thread direction.

Bye the way I am Out for trip tomorrow. Any one from Pune want to join me for "Shivaneri +Malshej " is welcome. Next time i will declare it in advanced.
Do we put such events as separate thread. If yes which one :help:
 
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Voted yes! Actually mileage depends on a variety of factors. My dad gets 14.5kmpl in my Safari in highways whereas i get only 13.5kmpl. So the driving style also matters a lot.

But regarding this poll yes you cannot the same mileage for an Alto/Swift and a Scorpio/ Innova/ Safari though the same person drives the car in the same manner.
 
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