Car talk--- horsepower vs torque

[rml]

I understand the techincal definition of Torque

How important is "Torque" in the real world?

If it is important, why do we only compare horsepower on cars?

thanks for any input but please don't tell me the formula to calculate "torque"

 

[PG]

thanks for any input but please don't tell me the formula to calculate "torque"


You do NOT calculate torque, but you can measure it. HP is calculated from torque and RPM. Torque is the independant variable.

When you hit the gas pedal and get thrown back in your seat so hard that you almost lose your grip on the steering wheel, THAT is torque.


edit: Torque is more important for trucks than say cars. When Dodge first put the Cummins Turbo Diesel in trucks, it only had 160 HP, but people loved it. Why? Because it had a solid 400 lb. ft. of torque. If one put some other high revving 160 HP engine in those trucks they would have a hard time pulling the truck, let alone a heavy trailer.

 

[KMurphy]

Torque is very important for hauling heavy loads. Semis for example have extremly high torque ratings and moderate horsepower. Torque is also what breaks the wheels loose on a launch. Horspower is how much energy an engine can produce or convert in a given time. Torque is similar to leverage.

 

[Supradude]

I'd rather have Torque than HP, torque is what gets you moving faster and in a tough jam can save you if you can manuever and pull the car through faster, cornering hould also be better with torque, HP contributes more to overall top end, and who needs that when the speed limit (CA t least) is 65 mph and basically every car on the market can do 70-80...

 

[vash]

My two recent cars are good examples of "real life" performance.

First car: 1998 Camaro Z28 with 5.0HO and 305 horses (dunno how much toruqe)
Second car: 2001 Acura CL-S with 260 horses and 245 pounds of torque (not 100% sure)

45 horses is the main difference in power, but the torque is the killer. When I had the Camaro, when I left my foot off the acceleration and put it back down, I still "felt" power. With the Acura, I feel that I lose a bit of power as soon as I take my foot off the gas (quite common in Southern Cali).

On hills, I would have to give more gas to my Acura to keep it from slowing down too much, but with the Camaro, I would barely notice any change in the car's performance going uphill.

There are definitely more differences in the cars (FWD vs. RWD), but that's how I equate "real life" performance. Someone will check into this thread lay the smack down on the real difference (engine power vs. actual power at the wheels), but this is how I felt with torque and horse power.

vash

 

[tontod]

With a lot of cars, I've noticed that torque and HP are pretty close.

 

[convex]

it's all about meaty v8 torque

 

[Soybomb]

<< why do we only compare horsepower on cars? >>


We don't just compare horsepower Most true auto afficianados will compare horsepower and torque in relation to engine speed.

Its very important in the real world, its what gives your car pulling power, and &quot;that certain feeling&quot;

 

[Rent]

&quot;Horsepower is how fast you hit the wall, torque is how much of it you take with you&quot;

I can't remember where I read that.

I don't know why anyone would debate that they want all hp and no torque or the opposite. Its the mixture of them that makes it fun to compare cars today

 

[Emulex]

torque will throw your ass in the seat and not let you reach forward.

It takes both to win a race. Torque is much more important with an AWD or RWD car. A lot of torque with FWD usually results in wheelspin. Wheelspin loses races.

It also depends on where you want to drive your motor daily. Those vtec honda's have to stay around 4000-5000 rpm's to move quickly. A torquey 4 cylinder like a TDI or Turbo 1.8 can move just as quickly at 2000-2500 rpm's.

Personally, i can't stand buzzy 4 cylinders that have to be wound out to move. Also generally speaking, the lower the rpm's you utilize, the less gas you'll use.

 

[LemonHead]

Horsepower
Torque and energy

Hope that helps

 

[rml]

http://www.howstuffworks.com/fpte.htm

This is the first site I looked at with www.google.com

It does not give me satifaction at all.

I like the replies here better

 

[Pacfanweb]

Torque and horsepower are directly related to each other. You can't have one and not the other.

In other words, say a 350 Chevy engine has 300 horsepower/275 ft/lbs at 4000 rpm.
You can't do anything to change the horsepower at that rpm and keep the same torque.

Torque is always better, but generally speaking, peak torque occurs at a much lower rpm than does peak HP.
Example: Old Buick 455 engines had 300+ HP but a whopping 510 ft/lbs torque. This is why those old cars pull so well in spite of their weight. That peak came under 3500 rpm.
If that same 300+ HP peak was at 5500 rpm, there would be much less torque.

This is why smaller engines have higher HP peaks and less torque. They have to rev higher to get the HP, and therefore produce less torque.

For street driving, a high torque engine is what you want. It can get you moving with much less effort.

 

[Viperoni]

Very interesting read

 

[JACKHAMMER]

<< Wheelspin loses races. >>



I disagree. First torque matters in all types of drive trains, not just RWD. Second I like wheel spin, that is what the Mickey's are for

 

[SammyBoy]

<< Horsepower is how fast you hit the wall, torque is how much of it you take with you >>




hehe, good quote, and true,

nice radeon