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Discussion Starter #1
OK, this sounds like a newbie question, but actually I've been around for a while I'm just an idiot
What exactly is torque, and what does it mean in relation to say, 1/4 mile time? Is it more important than horsepower?
 

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Re: Torque? (ILLZ)

torque is basically the low-end/low band power of your engine. in a 1/4 it matters because it will determine the power of your start
 

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Re: Torque? (JonnyBoy-17)

"Torque wins races, horsepower sells cars."
Ever wonder why a huge full-size pickup can jump off the line? Torque!!!
 

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Re: Torque? (AllMotor8v)

quote:[HR][/HR]"Torque wins races, horsepower sells cars."[HR][/HR]​
thats what people with no horsepower claim.
 

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Re: Torque? (ILLZ)

Check this webpage out

HowStuffWorks.com
In a nutshell, torque is rotational force while power (horsepower) is the rate at which this force is applied. More force (or torque) gets more done but more power gets it done faster
 

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Discussion Starter #7
Re: Torque? (bajan01)

ok so how important is torque in a 1/4 mile time? For instance is a car that produces 200 HP and 142 ft/lbs of torque going to run the 1/4 mile slower than a car with 200 HP and 175 ft/lbs of torque?
 

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Re: Torque? (ILLZ)

quote:[HR][/HR]ok so how important is torque in a 1/4 mile time? For instance is a car that produces 200 HP and 142 ft/lbs of torque going to run the 1/4 mile slower than a car with 200 HP and 175 ft/lbs of torque?[HR][/HR]​
no
let me bust out some physics as another analogy here: torque is acceleration and hp is velocity...the greater acceleration gets you to whatever velocity at a greater rate (my teacher would love me if he saw
)
 

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Discussion Starter #9
Re: Torque? (JonnyBoy-17)

ok so then in theory, the car with 175 ft/lbs of torque would beat the other car off the line but would be caught up with further down the track? Due to what? They have the same hp rating... (let's say for the sake of argument they are the exact same car...)
 

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Re: Torque? (ILLZ)

Horsepower is basically what you are looking for in 1/4 mile times. There are other factors here such as traction, gearing (which changes torque), drag, etc. but I won't talk about these.
If your engine produces a lot of torque across the powerband AND has a high redline, then you will make good 1/4 times. Torque by itself means nothing. Torque at a particular rpm means a hell of a lot. Saying an engine produces 200lb/ft torque means nothing. Saying an engine produces 200lb/ft or torque at say 2500rpm means a hell of a lot. That means the engine will produce a nice amount of hp at very low rpm. What this gives you is a better launch. Now if the torque curve is nice a flat then you will have a pretty linear horsepower. That will give you solid acceleration and if your rpm is nice and high then you will produce a lot of hp when you shift gears.
How much torque an engine produces and where the torque is distrubuted on the powerband will dictate where the car will preform best.
Torque peaking at low rpm and dying off early is more suited for city driving. No need to downshift often to take advantage of hp since a fair amount of hp can be had at virtually all rpms above idle.
A high flat torque curve will excel at most applications. Daily driving is nice and easy. Drag racing is a breeze. Race track driving is real nice. This is a very good overall engine. Generally you will find these characteristics in big displacement engines.
A somewhat peaky torque curve which peaks at mid rpm and an engine with an ability to spin really fast (rpm) will be more suited for track racing. Keeping the rpm up is real easy while racing on a track and that will take full advantage of the hp which comes on a little later than the previous examples. City driving is a little bit more of a choir since you will have to be downshifting a little more to get the engine to produce more hp. Drag racing is not totally suited for this engine, but it is not the best engine to be used for this. If the hp comes on a little later then you will have a slower launch.
I hope all this information was accurate. Since I am not a mechanical engineer, I could be WAY off base.
 

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Re: Torque? (flair.14)

i will add my 2 cents......
i will get beat up for this little comment but it is engineering... i sure that most of you are like me and you read on your competition and have looked at the new neon. on the dyno sheets that they provided the turbo neon produced 250 ft pds of torque at 2500 rpm. and 235 whp at 3000 rpm. with a quarter mile time of 14. car weight of 3200 pounds. now the reason they can achive that is the torque. this makes for a very VERY fast car. with the low trq and low hp it will fly.
lets do this one... i hate to do it but the 1.8t stock 190 ft pounds in a jetta 15.5 is what my buddy ran. chipped 195 whp 240 ft pounds. time 14.2 very fast high torque which makes for a very nice highway or high speed ummm track car
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this was just to show you how trq can play a very big roll in how fast car can be or how it cant be.
I have seen one turbo neon here in Indiana nad its in a show case. i dont know about all of you but that kind of torque at that rpm scares me. not to the point of me running the other way but to me giving neons a second look while on the umm track. with that said i have some work to do
 

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Discussion Starter #12
Re: Torque? (turbojeta3)

quote:[HR][/HR]i on the dyno sheets that they provided the turbo neon produced 250 ft pds of torque at 2500 rpm. and 235 whp at 3000 rpm. with a quarter mile time of 14. car weight of 3200 pounds. [HR][/HR]​
Is this a modded neon? Because if it's not the numbers are WAYYYYYYY off....a stock Neon produces 215 CRANK hp...not 235 whp...that would translate to aproximately 270 crank horse...I don't think they would sell a Neon with 270 hp for $16,000...check your numbers pal
also a Neon with 235 whp would run the 1/4 way faster than 14 flat...
 

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Re: Torque? (ILLZ)

Torque is the the ability of a vector force "F" which is a certain distance "R" to rotate a body. Simply T = Fsin(theta) (since the tangential force is all that matters). another definition is that the Net torque is the product of the Rotational inertia of an object and the corresponding angular accelleration (alpha). The standard unit for torque is the NM (Newton Meter) which is not to be confused with the Joule, since it is not the same as the energy unit of NM http://****************.com/smile/emthup.gif hope that helps


[Modified by Jettapimp, 2:17 PM 12-1-2002]
 

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Re: Torque? (ILLZ)

quote:[HR][/HR]i on the dyno sheets that they provided the turbo neon produced 250 ft pds of torque at 2500 rpm. and 235 whp at 3000 rpm. with a quarter mile time of 14. car weight of 3200 pounds.
Is this a modded neon? Because if it's not the numbers are WAYYYYYYY off....a stock Neon produces 215 CRANK hp...not 235 whp...that would translate to aproximately 270 crank horse...I don't think they would sell a Neon with 270 hp for $16,000...check your numbers pal
also a Neon with 235 whp would run the 1/4 way faster than 14 flat...[HR][/HR]​
Their numbers were slightly underrated by the factory....not the first company to do it.
 

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Re: Torque? (VW97Jetta)

I saw it too...the new neon was rated at 215 CRANK hp, and dynoed at 225. http://****************.com/smile/emthup.gif
 

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Re: Torque? (Boragirl03)

i dont think a linear hp graph would have a flat torque curve. That would mean hp is the integral of torque which i dont think is correct.
 

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Re: Torque? (Jettapimp)

flair.14 said it perfect. torque or horsepower without an rpm is useless.
a flat torque curve will give a linearly increasing horsepower curve, and yes, mathematically, power is the integral of torque. (integral of a constant is constant*x and x gives the slope). look in any physics book under work and power.
torque itself does not apply when calculating accelerations. a torque curve must be converted into a power curve for it to be useful, and then acceleration can be calculated.
if anyone is interested i'll post equations tomorrow of how to turn a power curve, gearing, tire size, weight into acceleration plots, fuel efficiency plots and whatever else you want.
and as a side note, engine designers don't compare tq and hp numbers. they use brake mean effective pressure as a comparison between dissimilar engines.
 

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Discussion Starter #20
Re: Torque? (Boragirl03)

quote:[HR][/HR]I saw it too...the new neon was rated at 215 CRANK hp, and dynoed at 225. http://****************.com/smile/emthup.gif [HR][/HR]​
http://****************.com/smile/emthup.gif
 
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