/o/ - Auto » Thread #5121570

[27 / 2 / ?]

41KiB, 500x412, A-One-Horsepower-Car-1232[1].jpg

Anonymous !PnW.aFiero Mon 08 Aug 2011 06:43:00 No.5121570 View View Reply Original Report

Hey /o/, I'm curious, what is horsepower? Like I understand the concept of torque and how it applies to a car and everything, but how exactly would you describe horsepower? What is it's actual purpose when you're talking about a cars horsepower?
Like more torque can tow a heavier load for example, what can more horsepower actually do? I'm just confused about the concept.

Mon 08 Aug 2011 06:54:00 No.5121615 Report

Quoted By:

90% don't know 9% can't explain it

The other 1% doesn't go to /o/

It's a measurement of how high a certain amount of weight can be lifted at a certain speed.

I don't fully understand it other than MOAR IZ BETTAR

Anonymous

Anonymous Mon 08 Aug 2011 06:59:00 No.5121635 Report

Quoted By:

power = torque * rotational speed

it's how quickly an engine can produce work.

inb4chan !PnW.aFiero

inb4chan !PnW.aFiero Mon 08 Aug 2011 07:00:00 No.5121639 Report

Quoted By:

horse power is the calculation of torque against rpm

ford apprentice !5zb/EKX0ks

ford apprentice !5zb/EKX0ks Mon 08 Aug 2011 07:02:00 No.5121651 Report

Quoted By: >>5121685 >>5121687

more power can tow more at a faster rate. Power is very important. horsepower is the measure of work at a rate. Torque is the amount of force. Like the torque you apply to a lugnut to break it loose. You can easily apply well over a 100lb-ft of torque onto a tight lugnut but you're applying that torque at a very slow rate so technically you're applying the same amount of torque that a motor in a car will produce to move a car but you're not applying that force at the same rate so you wouldn't be able to get a car moving up to 60 mph.

Just like when you use a long handle to apply more torque on a nut. An engine uses a transmission to multiply the torque to the wheels. So you can have an engine that produces a fair amount of power and little torque but will still apply lots of torque to the wheel with the proper transmission and rear gear.

If you understand how a transmission is there to multiply torque you don't need to have a massively torquey motor to do the job

Anonymous

Anonymous Mon 08 Aug 2011 07:07:00 No.5121685 Report

Quoted By:

>>5121651
Okay so with the lugnut thing...you say you're applying the torque to the lugnut at a very slow speed, if you were to jump on the bar you were removing it with you'd be moving the bar at a faster speed..is that the same concept since you'd be applying more force faster, since the bar would be turning faster?

Anonymous

Anonymous Mon 08 Aug 2011 07:07:00 No.5121687 Report

Quoted By: >>5121759

1 horsepower was a measurement coal miners in the 19th century used to describe how far a horse could carry a certain amount of wait in a certain amount of time. In another term, horsepower is just a measurement of raw power. 1HP = approx. 756watts so if you have a weird light bulb that has 756 watts, it's a 1 horsepower bulb. These days you just see horsepower as a basic way of measuring how good a car is.

Also, this:
>>5121651

>Torque is the amount of force. Like the torque you apply to a lugnut to break it loose. You can easily apply well over a 100lb-ft of torque onto a tight lugnut but you're applying that torque at a very slow rate so technically you're applying the same amount of torque that a motor in a car will produce to move a car but you're not applying that force at the same rate so you wouldn't be able to get a car moving up to 60 mph.

If you were able to to use your own 100lb-ft of torque at a much faster rate, you could move that car faster. So horsepower = rate while torque = power of the engine spinning

HowITripCode? !!DU22SQMj6dQ

HowITripCode? !!DU22SQMj6dQ Mon 08 Aug 2011 07:07:00 No.5121690 Report

Quoted By: >>5121734

Horsepower is defined as work done over time. The exact definition of one horsepower is 33,000 lb.ft./minute. Put another way, if you were to lift 33,000 pounds one foot over a period of one minute, you would have been working at the rate of one horsepower. In this case, you'd have expended one horsepower-minute of energy.

Google is a nifty thing

Anonymous

Anonymous Mon 08 Aug 2011 07:07:00 No.5121692 Report

Quoted By:

a car with one horsepower is the equivalent of a carriage being towed by one horse.
so 400hp is the power of 400 horses simultaneously pulling something

Anonymous

Anonymous Mon 08 Aug 2011 07:08:00 No.5121699 Report

Quoted By:

Horsepower sells cars
Torque wins races
Defense wins championships

Anonymous

Anonymous Mon 08 Aug 2011 07:16:00 No.5121734 Report

Quoted By:

>>5121690

This so hard

un/k/nownuser !4changtcqk

un/k/nownuser !4changtcqk Mon 08 Aug 2011 07:27:00 No.5121759 Report

Quoted By: >>5121769

>>5121687
>horsepower as a basic way of measuring how good a car is.

Only americans do that.

Anonymous

Anonymous Mon 08 Aug 2011 07:29:00 No.5121769 Report

Quoted By:

>>5121759
don't murrikans use torque for that?

Anonymous

Anonymous Mon 08 Aug 2011 07:30:00 No.5121775 Report

Quoted By:

Horsepower is how fast you hit the wall,
Torque is how far you take the wall with you.

Anonymous

Anonymous Mon 08 Aug 2011 07:54:00 No.5121899 Report

Quoted By: >>5122020

>>5121570

You can not create torque without horse power
That's why you have power bands in engines

Say your car is at idle, it is only doing 700 rpm, which the rate of power produced is only enough to keep the crank spinning along with the minimal torque

rev it up a little, and you increase that rate of power by having more combustions strokes in the one minute, basic math tells us force = mass x acceleration
Because you have more kicks of power in less time, the faster the crank will spin. The force of the rotation (other wise know as torque) increases. The higher the revs, the more torque produced.

If it doesn't make sense let me know.

Anonymous

Anonymous Mon 08 Aug 2011 08:15:00 No.5122020 Report

Quoted By:

>>5121899
That makes sense, but if the higher the revs means the more torque, then why do some cars like diesels make so much torque down low, and some make more torque up high? And if horsepower is based on torque, why do some cars end up with such a big split between where they make max horsepower and max torque?

Anonymous

Anonymous Mon 08 Aug 2011 11:22:00 No.5122995 Report

Quoted By: >>5123000

Begin by understanding the somewhat abstract concept behind torque: force.
If you can imagine pushing on a block, you're thinking of force. If you can imagine this force being applied in a turning / circular / angular way, such as pushing a spanner, you're thinking of torque.
Congratulations, you now know what torque is.

Now understand the somewhat abstract concept behind rotational speed: speed.
If you can imagine travelling a certain distance over a certain period of time, you're thinking of speed. If you can imagine this speed in a turning / circular / angular direction, you're thinking of rotational speed.
Congratulations, you now know what rotational speed is.

Now understand that power (horsepower) is a concept derived from speed and force, and a description of overall effort. Speed x Force, if you please.
In the world of cars and engines, it's difficult to talk usefully about torque without also talking about rotational speed (essentially RPM). When torque is mentioned, it is implicit that torque is being generated by either the engine or the wheels while turning at a certain rotational speed.

It helps to think about gears / gearing, and how they work.
You turn one gear at a certain rotational speed, with a certain amount of torque: the other gear turns at a different rotational speed, with a different amount of torque.
The amount of "effort" (i.e. power) put into one gear is the same as the amount of power that comes out of other. Say you're trying to propel a 1:2 fixed gear bike, wherein the wheels are as large as the diameter of the pedals. Using X amount of force, you turn the pedals at Y speed. You are putting in XY power. The bike experiences X/2 the amount of force you put in, and consequently ends up moving at 2Y speed. It is producing 2(XY)/2 = XY power.

Anonymous

Anonymous Mon 08 Aug 2011 11:23:00 No.5123000 Report

Quoted By:

>>5122995
To bring this all together:
Imagine turning a two meter long spanner with 150 newtons (pushing on something with ~15 kilograms of weight) of force in a circle once every 20 seconds (i.e. 3 RPM). You're producing 300nm (~221 lb/ft) of torque: incidentally, more than many family sedan engines. You're only producing, however, 0.94kW (1.26 hp) of power.
Say you tried to hook yourself up to the wheels of a family sedan and tried to power it at 60 km/h (~37 m/h). Using gears: you'd be producing NOT ENOUGH TORQUE AT THE WHEELS TO KEEP IT AT THAT SPEED, FUCK MATHS I'M TIRED

If you tried to do the same with, lets say, a motorcycle engine making 115nm (~85ft lbs) @ 10000 RPM: you'd be making DEFINITELY ENOUGH TORQUE AT THE WHEELS TO KEEP IT AT THAT SPEED.

TL:DR
TORQUE AT THE WHEELS AT A GIVEN SPEED TRANSLATES DIRECTLY INTO ACCELERATION AT A GIVEN SPEED. HORSEPOWER IS A DESCRIPTION OF TORQUE AT A GIVEN SPEED. GEARING LETS YOU TRADE TORQUE FOR SPEED AND VICE VERSA BETWEEN THE ENGINE AND THE WHEELS.

TL:DR the TL:DR
HORSEPOWER IS THE ONLY THING THAT MATTERS.

Anonymous

Anonymous Mon 08 Aug 2011 11:27:00 No.5123011 Report

Quoted By:

http://sfw.chanarchive.org/request_votes
Hmm, good thread /o/.
Let's keep this here for a while.

!fO.oGkEwC.

!fO.oGkEwC. Mon 08 Aug 2011 11:29:00 No.5123022 Report

Quoted By: >>5124341

lame ass terms

torkz brah is how far you will take the wall with you after you hit it

horse power is how fast you will hit the wall

all horsepower does is make the wheels spin faster

Anonymous

Anonymous Mon 08 Aug 2011 11:34:00 No.5123032 Report

Quoted By: >>5124367 >>5124375

Horsepower is Torque multiplied by RPM divided by 5252.
It is a number that doesn't physically exist. It is a representation of torque versus rpm. For example a high revving engine that has a low max torque, could easily have the same horsepower as a low revving torque monster.

Anonymous

View Same Google ImgOps iqdb SauceNAO joker clapping.gif, 235KiB, 390x269

Anonymous Mon 08 Aug 2011 22:16:00 No.5124341 Report

Quoted By: >>5124413

>>5123022

Anonymous

Anonymous Mon 08 Aug 2011 22:23:00 No.5124367 Report

Quoted By:

>>5123032

>power doesn't exist
hard to start with what you're thinking here. power is definitely measurable

>0.522 or whatever
yeah this is for specific units

Anonymous

Anonymous Mon 08 Aug 2011 22:25:00 No.5124375 Report

Quoted By: >>5124438

>>5123032

>For example a high revving engine that has a low max torque, could easily have the same horsepower as a low revving torque monster.

oh i see. you have no idea what you're talking about

Anonymous

Anonymous Mon 08 Aug 2011 22:30:00 No.5124397 Report

Quoted By: >>5124438

When you see X horsepower and Y Torque, horsepower is how much power the engine can make and torque is how well it does it.

But horsepower in itself is a unit of measurement, or something fuck I don't know.

SKkeeterZ !fO.oGkEwC.

SKkeeterZ !fO.oGkEwC. Mon 08 Aug 2011 22:35:00 No.5124413 Report

Quoted By:

>>5124341

>thanks to /o/ I now know

Anonymous

Anonymous Mon 08 Aug 2011 22:41:00 No.5124438 Report

Quoted By:

>>5124397
>torque is how well it does it
Naw man. Peak torque at a given RPM is, at best, a vague indicator of a cars powerband.

>>5124375
I don't think he does know what he's talking about, but his statement is essentially true

Capcode	All Only User Posts Only Verified Posts Only Moderator Posts Only Manager Posts Only Admin Posts Only Developer Posts Only Founder Posts
Show Posts	All Only With Images Only Without Images Only Spoiler Images Only Non-Spoiler Images
Deleted Posts	All Only Deleted Posts Only Non-Deleted Posts
Ghost Posts	All Only Ghost Posts Only Non-Ghost Posts
Post Type	All Only Sticky Threads Only Opening Posts Only Reply Posts
Results	All Grouped By Threads
Order	Latest Posts First Oldest Posts First

On these archives

Your latest searches