How do you increase Torque?

[johnnynumfiv]

Gives you low end grunt, gets you off the line, etc.

[nissangtr]

well what i understand when u talk about torque its how fast can u get speed, and thats whan im looking for, i got honda civic Si 2000 and i just have a cold air intake system (iceman) and i installed a throttle body but i would really want to get something besides a turbo to get more torque but i would like to feel a difference...thx

[revetec]

Originally Posted by Alastor

I disagree. Technically the change in pressure and volume within the piston cylinder is doing work. This work takes place over some time interval and therefore can be equated to a power. The pressure exerts a force on to the piston which generates a torque on the crankshaft.

So really an engine starts with power and creates torque and rpm.

Also, I don’t see how torque alone is better than power, in terms of performance figures?

A dyno only measures torque. A simple calculation X RPM gives you the power figure which is displayed.

You have pressure in a cylinder but the work is transfered to the crank via a connecting rod. This delivers torque or turning force to the crank. The higher the Revs the more work is done per minute so we call this power. A bigger throw on the crank the bigger the torque lever. A bigger bore provides more pressure on the crank which increases torque also.

But:

A good breathing engine provides a better torque at higher RPM which gives you more power because the power calculation is torque X RPM. To put it a different way: Greater RPM with good torque gives higher power.

The higher the torque at lower RPMs equates to higher efficiency. This is because less fuel is burnt (Lower RPM) to produce the pulling power.

Power and torque go hand in hand. Small engines need high revs to produce good power because of the lower torque, and larger engines have higher torque at lower RPMs so don't need to Rev as high. Different engines for different applications. One thing to note though: The higher the Revs the more frictional losses.

This is why turbos are so good, More pressure on the piston at lower revs gives better torque and power at lower RPMs. Let's say that you are pushing more in the cylinder with a turbo and then compare it with a normally aspirated engine with higher RPMs. It should be about the same in effect, but it has less frictional losses because the RPMs are less.

[jediali]

I guess you want to keep a good mean effective pressure throughout the operating range. Revtec has covered all the bases really but without Forced induction you cant really increase the torque/litre much. NA engines can use exhaust backpressure to draw air in (reverse supercharging) but this would require VVT and clever timing to work , and also a high exhaust gas speed.

[Alastor]

Originally Posted by revetec

A dyno only measures torque. A simple calculation X RPM gives you the power figure which is displayed.

You have pressure in a cylinder but the work is transfered to the crank via a connecting rod. This delivers torque or turning force to the crank. The higher the Revs the more work is done per minute so we call this power. A bigger throw on the crank the bigger the torque lever. A bigger bore provides more pressure on the crank which increases torque also.

But:

A good breathing engine provides a better torque at higher RPM which gives you more power because the power calculation is torque X RPM. To put it a different way: Greater RPM with good torque gives higher power.

The higher the torque at lower RPMs equates to higher efficiency. This is because less fuel is burnt (Lower RPM) to produce the pulling power.

Power and torque go hand in hand. Small engines need high revs to produce good power because of the lower torque, and larger engines have higher torque at lower RPMs so don't need to Rev as high. Different engines for different applications. One thing to note though: The higher the Revs the more frictional losses.

This is why turbos are so good, More pressure on the piston at lower revs gives better torque and power at lower RPMs. Let's say that you are pushing more in the cylinder with a turbo and then compare it with a normally aspirated engine with higher RPMs. It should be about the same in effect, but it has less frictional losses because the RPMs are less.

My point was just that the pressure acting on the piston alone was not enough to do work, the piston must also move.

So even if you have a given pressure acting on the piston and the resulting torque around the crankshaft, the engine is not doing any work unless the piston is moving.

Obviously, power is the measure of both pressure (pressure as a function of piston area) and piston motion (where motion is a rate of change).

But this thread is so old, I am not sure if my original comment was even that relevant.

[Quiggs]

Originally Posted by nissangtr

well what i understand when u talk about torque its how fast can u get speed, and thats whan im looking for, i got honda civic Si 2000 and i just have a cold air intake system (iceman) and i installed a throttle body but i would really want to get something besides a turbo to get more torque but i would like to feel a difference...thx

NOS. Two of 'em. The big ones. And you need it by tonight.

[roosterjuicer]

the best way to get torque is to get a bigger motor!

[BradG]

Originally Posted by Bob

Yeah that was pretty bad on my part I'm sorry it was early and I was up until 5 last night on cruise boat so I'm pretty out of it... my bad.

anyways, torque is the force that is applied at a certain distance (radius) of rotation, so its a much greater factor in acceleration than horsepower, but once you pass a certain limit, which is different for every car/tire setup/driving conditions, the amount of force at the wheels is more than the maximum force of friction with the road, and any more torque is useless.

It all depends on how you look at it. Tire size (overall radius) does make a difference in the potential force at the ground (which is really what you're interested in anyway). If you consider this, then it also makes a difference on the effective "resistive torque" from the ground. This is important when considering traction limited situations.

[jediali]

Originally Posted by Quiggs

NOS. Two of 'em. The big ones. And you need it by tonight.

amateurs don't use nitrous oxide, I've seen the way you drive! you'll blow yourself to pieces.

both statements where from fatf.

[Bob]

Originally Posted by jediali

amateurs don't use nitrous oxide, I've seen the way you drive! you'll blow yourself to pieces.

Was that a fast and the furious quote? zomg

that being said, a nice 150 shot would be very nice for my car

[hightower99]

I don't get the fascination with torque...

then then then

then:

Power does everything, from accelerating to maintaining top speed. Torque is simply a factor involved and getting hot under the collar about peak torque figures is ridiculous at best.

A 500HP engine is going to do exactly the same anout of work and get you exactly the same performance whether it produces 100lbs-ft. or 2000lbs-ft. of torque.

BTW: For torque at the wheels I would guess you want to feel a bigger rush as you accelerate right? well then you want more thrust at the wheels (not torque being an instant factor that gets you nothing on its own). Easy to do. Just put a differential in the has a bigger ratio (You want 4:1 instead of 3:1) this will kill some top speed but really quicken acceleration times. Also try mounting wheels with a smaller OD (outer diameter) because the bigger this is the less thrust you but into the ground, not to mention the increased inertia effects of a wheel with a larger OD.

then:

[Cyco]

Originally Posted by hightower99

Power does everything, from accelerating to maintaining top speed. Torque is simply a factor involved and getting hot under the collar about peak torque figures is ridiculous at best.

Well that would be correct, if power wasn't calculated form torque initially......

[henk4]

Originally Posted by hightower99

I don't get the fascination with torque...

because maximum torque is something you always experience in daily driving and maximum power only comes in rarely when you rev to the floor......

[SlickHolden]

Originally Posted by h00t_h00t

Meh, I drove a 6/7 litre I6 tractor with 180hp and 800nm of torque

But you didn't drive it to McDonald's with 5 mates and A/C on with leather trim

[revetec]

Originally Posted by hightower99

A 500HP engine is going to do exactly the same anout of work and get you exactly the same performance whether it produces 100lbs-ft. or 2000lbs-ft. of torque.

That's OK if you were at say 6,000rpm all the time. But you are not. You drive through a range of say 2,000rpm to 6,000rpm.

I pose to you that a steam train has 5000Nm of torque but only 300kW. It can pull a 20 carriage train from a standing start quite easily. Put your 300kW car with 500Nm in front and try to pull it. You wont move it easily.

Torque is all important at the lower rev ranges for acceleration while horsepower is low. You may have 300kW on tap, but at what RPM. If it is at 6,000rpm the power at 3,000rpm may be 150kW. So if the torque is higher at lower RPM then not only is your power going to be higher at this point but it will accelerate quicker to 6,000rpm. What I am trying to say is that if you provide higher torque at a lower RPM then your power curve will rise faster and be more flat through the midrange making it accelerate stronger through the rev range. So peak power is not as important as a wide flat power range provided by a good torque curve if you want the fastest time between A and B.

Similarly, if you are cruising in a high gear and you approach a hill. The lower torque engine will have to gear down to increase horsepower before the high torque engine has to. It's all about driveability and efficiency. A flat torque curve is most desirable in production cars as it gives a smooth even acceleration. People who like to drive harder may like the power peak feel. The heavier the vehicle, the more torque is desirable.