torque or horsepower

[tom d]

this is a stupid question, but we'll forgive you.

torque is real and can be measured and at any rpm, horsepower is not!

horsepower is a made up term and has absolutly no value except for arguing about what is better, horsepower or torque. James Watts (recognize that name?) coined the term so that he could sell steam engines.

horsepower is the amount of work that a horse can do during a work day, so to say that your car has 180 HP means that your car can do the work of 180 horses in one day....seriously?

horsepower is an irrevealant term and the fact that we cling to it like a mother's breast is silly and says a lot about how stupid we are as americans, most of the rest of the world measures a motor's output in watts, not horsepower!

[slammin.e28]

I, as many on here, like breasts, so we cling to HP.

However, you are right. Torque is real. HP is imaginary. I love hitting ricers with that. 99.999% are too stupid to know the difference.

[Bullwings]

^ Ok, then kW with peak kW rising all the way to redline.

[digger]

its a force that accelerates a vehicle, so just to confuse people its all about how much hp is available because that is what generates torque in the axles and subsequently the force

remember the engine torque gets multiplied through the gearbox and diff at the expense of speed.

the people who are advocates for torque dont realise they are actually liking the fact that the hp is available at lower engine speeds and is therefore more accessible.

due to finite gearing the shape of the hp curve is important if you ran a perfect CVT you would just run it at peak hp rpm

[downforce22]

cvt?

[Addison325ix]

Possibly this?
CVT
A continuously variable transmission (CVT) is a transmission that can change seamlessly through an infinite number of effective gear ratios between maximum and minimum values. This contrasts with other mechanical transmissions that offer a fixed number of gear ratios.

[digger]

Possibly this?
CVT
A continuously variable transmission (CVT) is a transmission that can change seamlessly through an infinite number of effective gear ratios between maximum and minimum values. This contrasts with other mechanical transmissions that offer a fixed number of gear ratios.

yep, maximum performance potential with "infinitely" varying gear ratios would be achieved at peak hp rpm and not at the peak engine torque rpm

[fiveightandten]

this is a stupid question, but we'll forgive you.

torque is real and can be measured and at any rpm, horsepower is not!

horsepower is a made up term and has absolutly no value except for arguing about what is better, horsepower or torque. James Watts (recognize that name?) coined the term so that he could sell steam engines.

horsepower is the amount of work that a horse can do during a work day, so to say that your car has 180 HP means that your car can do the work of 180 horses in one day....seriously?

horsepower is an irrevealant term and the fact that we cling to it like a mother's breast is silly and says a lot about how stupid we are as americans, most of the rest of the world measures a motor's output in watts, not horsepower!

Horsepower was originally invented to compare the power output of steam engines to the amount of work a horse could do. That makes sense in theory, as you'd have to compare the new technology to the old to have a grasp on comparing them.

Though, trying to put a number (even an average over time) to the amount of work an animal can do is utterly ridiculous. There are so many variables, the conversion factor (1HP = 746W) isn't very meaningful when comparing machines to animals. Clinging to this antiquated unit of power measurement this long has clearly gone past the original intent of the term.

That being said, it's been used here for so long that it's clearly made itself relevant. It's probably here to stay until the ICE dies and electric vehicles are all we have. When using it to compare machines to machines, it gets the job done. And quite frankly, it sounds cooler than the "watt"

[tom d]

its all about how much hp is available because that is what generates torque in the axles and subsequently the force

digger are you really trying to tell us that torque is a byproduct of horsepower? as mentioned above, the formula for calculating the horsepower of a given engine is to first measure the torque output of the engine, multiply it by the engine's rpm and then divide the sum by 5252.

the key words here are measure and calculated, torque can be measured, horsepower can only be calculated!

if you disagree with the above then I would suggest visiting your highschool and slapping your physics teacher.

[CoreyZ]

Petition to rephrase the OP:

Where do you want power? Low end, mid range, top end?

[digger]

digger are you really trying to tell us that torque is a byproduct of horsepower? as mentioned above, the formula for calculating the horsepower of a given engine is to first measure the torque output of the engine, multiply it by the engine's rpm and then divide the sum by 5252.

the key words here are measure and calculated, torque can be measured, horsepower can only be calculated!

if you disagree with the above then I would suggest visiting your highschool and slapping your physics teacher.

what i said was that if i make hp I can generate torque in the output axles through gearing. the torque in drive axle is simply proportional to power transmitted divided by the rpm

Sorry saying one is measured and one is calculated is just useless semantics that doesn’t change the fact that the vehicle with more useable hp in the operating band will win every single time (subject to traction).

Torque at the engine is very misleading without considering rpm, that's why hp is a useful concept to understand. A vehicle with a higher hp engine can always run more aggressive gearing than a vehicle with a lower hp engine and that’s why useable hp wins.

i can take a 100 hp, 100 lb-ft motor operating at 5,252 rpm and gear it to 10,000 lb-ft with a 100:1 gearbox. the consequence is the output rpm lowers by the same ratio to 52.52 rpm.

now i take a 200 hp motor with same 100 lb-ft torque spinning at 10,504 rpm and gear it to same 52.52 rpm which requires a 200:1 gearbox and suddenly i have 20,000ft-lb torque at the output shaft at the same output speed.

Wow the wonders of hp and being a measure of ability to do useful work in a given time…..

think of the output speed as the road speed, so at the same road speed I have twice as much axle torque and therefore twice as much propulsion force and my motor doesn’t even make any more torque it just spins faster and maintains torque.

[lukeADE335i]

Who gives a shit?

Most E30s have neither, but they're still tons of fun.

Unless you throw an M30 in there, then you've got enough :)

Took a mate for a spin in mine the other day, and he was blown away by how effortlessly the car pulls in any gear & he's owned plenty of domestic V8s, hot 6's etc.

For a road car the trick is plenty of power at low rpm & a torque curve is reasonably flat across the rev range so the engine is very flexible. For the track, obviously a peaky engine is fine. Horses for courses.

My sister's Hyundai i30 diesel has heaps of torque, at very low rpm but is no fun at all, at any speed. The 4.5L / 100 economy she gets (52mpg) is nothing to sneeze at though ;)

[Wh33lhop]

digger are you really trying to tell us that torque is a byproduct of horsepower? as mentioned above, the formula for calculating the horsepower of a given engine is to first measure the torque output of the engine, multiply it by the engine's rpm and then divide the sum by 5252.

the key words here are measure and calculated, torque can be measured, horsepower can only be calculated!

if you disagree with the above then I would suggest visiting your highschool and slapping your physics teacher.

Oh shut up. Possible torque at the wheels at any given speed is a product of the maximum power the engine puts out. That's why an S2000 isn't slow at speed and that's why we rate engines in horsepower and not just torque. Torque is great but without an engine speed to go with it it's irrelevant.

If you are measuring it at the wheels, power is actually easier to calculate than torque, because you don't have to take gearing into account; it's done that for you.

[Mr. Tasty]

Fuel economy.

so torque

[TobyB]

I want a big fat torque curve. and gearing. Infinite gearing.

Although CVT's are boring as shit to drive.

I vote this thread 'bummerforums worthy'.

t