The engine capacity or volume is measured by a metric unit referred to as cubic centimeters or simply cm³, commonly abbreviated as “cc”. It is the unit of measuring the volume of a cube having a size of 1cm x 1cm x 1cm. CC is also known as ‘engine displacement’. It means the displacement of the piston inside the cylinder from the Top Dead Centre (TDC) to the Bottom Dead Centre (BDC) in the engine’s one complete cycle.
The engine volume is also measured in liters corresponding to cubic centimeters. If an engine has a capacity of say 1000cc or 1000 cubic centimeters, then the capacity of that engine is 1 liter. For example, 1000cc = 1000cm³ = 1 liter = 1.0L or 800cc = 800cm³ = 0.8 liter = 0.8L.
How to measure engine capacity or engine volume
To calculate the volume of an engine you can use the formula:
V = π/4 x (D)² x H x N
Where, V = Volume, D = Bore Diameter, H = Stroke Length, N = No. of cylinders
It is the combined capacity for all cylinders of the engine added together while it completes its one cycle. For example, if a four-cylinder engine has a capacity of 1000cc or 1.0L, that means all the four cylinders can together accommodate a maximum of 1000 cubic centimeters or 1.0L of the volume of air (or the air-fuel mixture) in them. If the engine has only one cylinder, then that lone cylinder will accommodate all of the 1000cc or 1.0L of air inside it. By the way, the world’s first automotive – the Mercedes-Benz MotorWagen featured a single-cylinder 1.0-liter engine (954cc to be precise) to power it.
How engine capacity affects its performance
The engine’s capacity plays an important role in determining various engine outputs such as engine power, torque, and mileage. It is the volume, or in other words, the space available inside the cylinder to accommodate air-fuel mixture for burning. Consider that it is just like a drum filled with water. The bigger the drum, more the water it can accumulate and guzzle. Similarly, an engine with a higher capacity sucks more air into the cylinder.
As the volume of the air grows, the fuel system also proportionately increases the corresponding quantity of fuel to the engine. As the amount of fuel for burning increases, it also increases the power output. Hence, in simple words, the power output of an engine is directly proportional to its capacity in a conventional engine design. Supplying more fuel to the engine increases its power and also its fuel consumption.
As the volume of the cylinders increases, the power output also increases. But eventually, this reduces the mileage. Hence, in that context, the mileage of the car is inversely proportional to the engine capacity in a conventional design. The manufacturers keep upgrading the petrol engines and strike a balance between power and mileage to achieve both performance and efficiency.
How engine capacity affects mileage
Typically, the cars with petrol engines of the best fuel mileage come in the zone of up to 1000cc. Those with capacities of 1000cc to 1500cc have better mileage figures. Whereas engines with displacement from 1500cc to 1800cc have a moderate fuel average range. Those with capacities from 1800cc to 2500cc have a lower fuel average range and the engines above 2500cc have the least mileage among all.
| Typical data ranges for petrol four wheelers | |||||
| No. | Engine capacity | Fuel mileage (Petrol) | Overall range (Max)* | Power output* | Applicable vehicle segments |
| 1. | Up to 1000cc | Best | Above 20 km/L | Up to 70 BHP | Small cars, hatchbacks. |
| 2. | 1000cc to 1500cc | Better | 20 to 17 km/L | 70 to 110 BHP | Family cars, entry level saloons, sub-4 meter vehicles. |
| 3. | 1500cc to 1800cc | Moderate | 16 to 13 km/L | 110 to 170 BHP | Mid-size cars, small wagons. |
| 4. | 1800cc to 250cc | Lower | 12 to 9 km/L | 170 to 230 BHP | Semi-luxury cars, wagons, MPVs, SUVs. |
| 5. | Above 2500cc | Least | Up to 9 km/L | Above 230 BHP | SUVs, sports cars, high-end luxury cars. |
Note:
*These values are indicative only. Actual values may vary from models to models and according to specific engine designs and does not include fuel injection, hybrid technology and electric vehicles.
An almost identical set of rules apply to the smaller carburetor engines for bikes. Typically, the bike engines with the best fuel average come in the range of up to 110cc. Engines from 110cc to 150cc have better mileage figures. Engines with capacities from 150cc to 200cc have a moderate fuel average range. The engines with a capacity from 200cc to 500cc have lower mileage. Engines above 500cc have the least mileage among all.
| Typical data ranges for petrol two wheelers | |||||
| No. | Engine capacity | Fuel mileage (Petrol) | Overall range (Max)* | Power output* | Ideal usage |
| 1. | Up to 110cc | Best | Above 80 km/L | Up to 10 BHP | Best for low fuel budget, frequent city travel. |
| 2. | 110cc to 150cc | Better | 80 to 60 km/L | 10 to 15 BHP | Daily commuting mainly within the city. |
| 3. | 150cc to 200cc | Moderate | 60 to 40 km/L | 15 to 20 BHP | Mix of city and highway travel. |
| 4. | 200cc to 500cc | Lower | 40 to 25 km/L | 20 to 30 BHP | Better for highway travel, occasional withing city travel. |
| 5. | Above 500cc | Least | Up to 25 km/L | Above 30 BHP | Performance, off-roading, leisure travel. |
Note:
*These values are indicative only. Actual values may vary from models to models and according to specific engine designs and does not include fuel injection, hybrid technology and electric vehicles.
Conclusion
Hence, the engine cc displacement is a crucial factor while buying an automobile. You should decide the displacement thoughtfully by analyzing the intended purpose or the end usage of the vehicle. So that, it doesn’t disappoint you with the performance of the vehicle which you select.
