What does CC and horsepower actually mean in cars?


What does CC and horsepower actually mean in cars?

In: Engineering

CC means cubic centimeters and describes the volume of the engine cylinders.

Horsepower is a measure of the rate which work can be done. 1 horsepower means that you can move 550 lbs 1 foot in 1 second. 2 horsepowers would either be 1100 lbs/1 ft/1 second, 550 lbs/2 ft/1 second, 550 lbs/1 ft/0.5 seconds or any combination thereof.

To expand on CCs, when an engine is, say, 2000 cubic centimeters, that means that each piston “displaces” 2000 divided by the number of cylinders it has.

So for a 4 cylinder engine, each cylinder would displace 500cc.

What displacement means is the volume of the space within the cylinder that the piston moves through. To get that number, you take the bore of the cylinder (the diameter), then use good old pi to figure out the area, then multiply by the stroke of the piston (how far it moves up and down in the cylinder).

So each time a piston cycles in our 2000cc four cylinder engine, it displaces 500cc of air, and does this four times a complete engine cycle, for 2000cc of total displacement.

Horsepower is a measure of “power”, which is a term in physics that describes doing one job in a period of time. The shorter the time, the more “powerful” that machine is.

For example, I can carry two buckets of water at the same time, one in each arm. My mom can only carry one bucket, using both hands to hold it. If we need to fill up the same tank with water, I will finish faster because I can carry twice the amount. I will fill up two buckets, and she will only fill up one. After three trips, I filled up 6 buckets, and she was only able to carry 3 buckets in that time.

If we need to fill up 10 buckets, and each trip takes 1 minute, I will finish in 5 minutes (5 trips), while she will finish in 10 minutes (10 trips). I was able to do the job faster, in a shorter time, therefore, I have more “power”. If my mom has a 5 HP engine, I have a 10 HP engine.

As others have pointed out, CC refers to engine displacement. You also commonly see this measured as cubic inches as well as liters. For example, you might see a 1960’s Ford Mustang advertised with a “289.” This refers to an engine displacing 289 cubic inches. You might also see a later-model Mustang advertised as a 5.0, referring to 5 liters (more or less) of displacement.

In short, larger engines displace more volume. As any gear head will tell you, when it comes to performance [there’s no replacement for displacement](https://www.youtube.com/watch?v=pHb4KH08bZs).

Originally horse power was derived from how much of a field a draught horse could plough in an hour, they would then see how much the tractor could plough. It was a highly inaccurate measurement. This is the reason most of the world changed to kilowatts, which is a measurement of energy. Both refer to how fast an engine can apply it’s torque in the automotive sense tho.

Im surprised that nobody has mentioned yet the fact that a power level of 1 **hp** is approximately equivalent to 746 watt (W) or 0.746 kilowatt (kW). If you’re into physics, that makes more sense.

Others have broken down the technicalities of cc and hp, but if you’re around car guys, it’s shorthand for “how powerful is your car?”

CC (cubic centimeters, or its American cousin, ci, cubic inches) is almost always directly related to power. The bigger the number, the more powerful your engine. Back in the muscle car days of the late 60s and 70s, you could roughly equate one cubic inch with one horsepower, so a “Chevy big-block 350” would make roughly 350 HP.

These days you’re more likely to hear displacement referred to in liters instead of cc or ci (smaller engines in ATVs or motorcycles will still use cc). There’s not much of a direct one-to-one for liters-to-horsepower as current engine technology is much more advanced than the 70s, but it’s not uncommon for a 6-liter V-8 engine to make well over 400 HP if it’s naturally aspirated (over 700 if it’s boosted with turbo or superchargers like a Dodge Hellcat). A Dodge Viper can make about 650 hp with a naturally aspirated 8.4 liter V-10.

Horsepower is not constant for a combustion engine. It can widely differ for the revolution per minute.

cc is cubic centimeters, its a sub unit o fliters and if i recall it descrubes the isplacement of the cylenders (i.e. if you dropped all the clenders to the bottom and filled them with water you would have xx cc or x liters. horsepower is a mesuremet of the peak power of the engine in its power. horsepower in the traditional sense was based off of the legitimate power of a horse- “one **horsepower** equals 33,000 foot-pounds of work per minute—that is, the power necessary to lift a total mass of 33,000 pounds one foot in one minute ” cars are actually mesured in BHP or break horsepower which is a different, automotive normalized power unit. it is called break cos it is mesured by breaking the engine on a dynamo and mesures the real output at the wheels with all the frictional losses involved whereas hp messures the output of the engine, BHP is always lower than HP

Horsepower can also describe how much fuel an engine can burn per second multiplied by some efficiency constant. Because of this an engine with more CC has can have more horsepower because it can hold more fuel and burn it quicker, assuming the same efficiency constant and same rpms.