Hooters crew
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From: Mandeville, La
Originally Posted by Kungfuhamster,Sep 20 2008, 06:02 PM
its cool man, its cool.
no, i hate when my fellow domestic guys assume since they have a larger engine, their car must be faster (i still get people that look at me in disbelief when i tell them a 4.6 makes more power than a 5.0)
as for my statement of "torque is a function of horsepower and displacement", that was, like you said...a basic statement. i was just saying that generally, a larger displacement engine will make more torque than a smaller one. of course, that isnt always the case, but generally.
as for commanding respect.....respect = 240hp from 2.0 liters of displacement.
btw, ill be heading up to Hooters at noon Sunday. i heard theres some kind of drift event at zephyr field? i dont know. if anyone comes up to Hooters thats cool. ill more than likely go inside first so i can get some food.
no, i hate when my fellow domestic guys assume since they have a larger engine, their car must be faster (i still get people that look at me in disbelief when i tell them a 4.6 makes more power than a 5.0)
as for my statement of "torque is a function of horsepower and displacement", that was, like you said...a basic statement. i was just saying that generally, a larger displacement engine will make more torque than a smaller one. of course, that isnt always the case, but generally.
as for commanding respect.....respect = 240hp from 2.0 liters of displacement.
btw, ill be heading up to Hooters at noon Sunday. i heard theres some kind of drift event at zephyr field? i dont know. if anyone comes up to Hooters thats cool. ill more than likely go inside first so i can get some food.
Which hooters are you going to?
And as for the 240hp with a 2.0L: I will soon be upwards of 500hp with a 2.0L
At ~2750lbs nonetheless! It's gonna be funnnn.
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From: Ocean Springs
Originally Posted by S2krazy2,Sep 18 2008, 09:23 PM
I guess the part that threw me off was "torque is a function of horsepower and displacement"... which I hope we all can agree is somewhat subjective and not completely true. While horsepower and torque are linear, one is not necessarily a function of the other, as they are two distinct values (one of power, and the other of force at a moment, i.e. power at work.)
I hated physics.
Not true either: horsepower is a direct function of torque (and engine RPM). HP = (TQ x RPM) / 5252
Torque is work (look at the units: foot-lbs), while Horsepower (power) is work over time (or torque over time... hence TQ divide by Minutes).
Torque itself, in an internal combustion engine, is a factor of many things, including displacement.
I loved physics
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From: Mandeville, La
[QUOTE=bky,Sep 20 2008, 09:56 PM] Not true either: horsepower is a direct function of torque (and engine RPM).
HP = (TQ x RPM) / 5252
Torque is work (look at the units: foot-lbs), while Horsepower (power) is work over time (or torque over time... hence TQ divide by Minutes).
Torque itself, in an internal combustion engine, is a factor of many things, including displacement.
I loved physics
Not true either: horsepower is a direct function of torque (and engine RPM). HP = (TQ x RPM) / 5252
Torque is work (look at the units: foot-lbs), while Horsepower (power) is work over time (or torque over time... hence TQ divide by Minutes).
Torque itself, in an internal combustion engine, is a factor of many things, including displacement.
I loved physics
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From: Ocean Springs
I'm not sure I follow: Power is, by definition, the rate at which work is done. Work is, by definition, a force applied over a distance. In angular terms, is simply
HP = (TQ x RPM) /5252, if the units for TQ are given in foot-lbs.
You said "While horsepower and torque are linear, one is not necessarily a function of the other, as they are two distinct values (one of power, and the other of force at a moment, i.e. power at work.)"
This implies that Torque is "force at a moment, i.e. power at work", which I don't understand at all. Power is defined by work: it is the rate at which work is produced. Torque is a force *around* a moment, not *at* a moment (unless you are using the word "moment" to describe time, like "a moment in time"). If you are referring to time, then you've got torque all wrong: torque doesn't involve time at all. Or, I've completely misunderstood you because you are using "moment" and "work" in layman's terms, not engineering terms.
Torque is a form of work, and dynometers don't measure horsepower directly: they actually measure torque. You *must* have an RPM signal in order to calculate horsepower. At any given engine speed (a constant), there is only one horsepower value. That's what I mean by "HP is a function of TQ". They are related to each other: in fact, they cannot be separated. This is also why HP and TQ graphs *always* interested each other in value at exactly 5252 rpm. Ah, maybe I am using "function" in layman's terms, not mathematical terms. Maybe I need to brush on my my math definitions.
HP = (TQ x RPM) /5252, if the units for TQ are given in foot-lbs.
You said "While horsepower and torque are linear, one is not necessarily a function of the other, as they are two distinct values (one of power, and the other of force at a moment, i.e. power at work.)"
This implies that Torque is "force at a moment, i.e. power at work", which I don't understand at all. Power is defined by work: it is the rate at which work is produced. Torque is a force *around* a moment, not *at* a moment (unless you are using the word "moment" to describe time, like "a moment in time"). If you are referring to time, then you've got torque all wrong: torque doesn't involve time at all. Or, I've completely misunderstood you because you are using "moment" and "work" in layman's terms, not engineering terms.
Torque is a form of work, and dynometers don't measure horsepower directly: they actually measure torque. You *must* have an RPM signal in order to calculate horsepower. At any given engine speed (a constant), there is only one horsepower value. That's what I mean by "HP is a function of TQ". They are related to each other: in fact, they cannot be separated. This is also why HP and TQ graphs *always* interested each other in value at exactly 5252 rpm. Ah, maybe I am using "function" in layman's terms, not mathematical terms. Maybe I need to brush on my my math definitions.
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From: Mandeville, La
Originally Posted by bky,Sep 22 2008, 07:34 PM
I'm not sure I follow: Power is, by definition, the rate at which work is done. Work is, by definition, a force applied over a distance. In angular terms, is simply
HP = (TQ x RPM) /5252, if the units for TQ are given in foot-lbs.
You said "While horsepower and torque are linear, one is not necessarily a function of the other, as they are two distinct values (one of power, and the other of force at a moment, i.e. power at work.)"
This implies that Torque is "force at a moment, i.e. power at work", which I don't understand at all. Power is defined by work: it is the rate at which work is produced. Torque is a force *around* a moment, not *at* a moment (unless you are using the word "moment" to describe time, like "a moment in time"). If you are referring to time, then you've got torque all wrong: torque doesn't involve time at all. Or, I've completely misunderstood you because you are using "moment" and "work" in layman's terms, not engineering terms.
Torque is a form of work, and dynometers don't measure horsepower directly: they actually measure torque. You *must* have an RPM signal in order to calculate horsepower. At any given engine speed (a constant), there is only one horsepower value. That's what I mean by "HP is a function of TQ". They are related to each other: in fact, they cannot be separated. This is also why HP and TQ graphs *always* interested each other in value at exactly 5252 rpm. Ah, maybe I am using "function" in layman's terms, not mathematical terms. Maybe I need to brush on my my math definitions.
HP = (TQ x RPM) /5252, if the units for TQ are given in foot-lbs.
You said "While horsepower and torque are linear, one is not necessarily a function of the other, as they are two distinct values (one of power, and the other of force at a moment, i.e. power at work.)"
This implies that Torque is "force at a moment, i.e. power at work", which I don't understand at all. Power is defined by work: it is the rate at which work is produced. Torque is a force *around* a moment, not *at* a moment (unless you are using the word "moment" to describe time, like "a moment in time"). If you are referring to time, then you've got torque all wrong: torque doesn't involve time at all. Or, I've completely misunderstood you because you are using "moment" and "work" in layman's terms, not engineering terms.
Torque is a form of work, and dynometers don't measure horsepower directly: they actually measure torque. You *must* have an RPM signal in order to calculate horsepower. At any given engine speed (a constant), there is only one horsepower value. That's what I mean by "HP is a function of TQ". They are related to each other: in fact, they cannot be separated. This is also why HP and TQ graphs *always* interested each other in value at exactly 5252 rpm. Ah, maybe I am using "function" in layman's terms, not mathematical terms. Maybe I need to brush on my my math definitions.
It would appear that you were misusing a mathematical term and I was not careful in my use of physics terms (I should have said "around a moment", as I was not implying that time was involved)... and I just don't feel like going to fix all of that! (Mr. Allen would kill me for giving up)
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From: Mandeville, La
Originally Posted by genghiskwong,Sep 23 2008, 08:42 PM
this brings back memories of the great color vs speed debate regarding the "torque" added by photons.....
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From: Mandeville, La
Originally Posted by FormerDatsun510Man,Sep 24 2008, 03:47 AM
I have to agree with Benson 
, very good concise explanation. I illustrated the relationship of torque and power and how they can independently model the acceleration of a vehicle in this little post I wrote years back. What I mean is that either one of them can be used to calculate the acceleration of a vehicle, and you will end up with the same answer... it is just a matter of the variables you need to solve the equations.
http://forum.miata.net/vb/showthread.php?t=127306
Bill
, very good concise explanation. I illustrated the relationship of torque and power and how they can independently model the acceleration of a vehicle in this little post I wrote years back. What I mean is that either one of them can be used to calculate the acceleration of a vehicle, and you will end up with the same answer... it is just a matter of the variables you need to solve the equations.http://forum.miata.net/vb/showthread.php?t=127306
Bill
