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Browse through the engine specifications of any vehicle, and you will find two metrics that are a measure of how strong, powerful, potent, amazing, great, competent, you-name-it, an engine is. These two measures are power and torque. Power is typically measured in Horsepower (hp) or Kilowatts (kW), and torque is measured either in Newton Metres (Nm) or Foot Pounds (lb-ft). You may be wondering what the difference between horsepower and torque is. There's a pretty poor explanation that's been going around for ages, stating that "horsepower is how hard you hit the wall, while torque is how far you take the wall with you". Let's turn to something a little more accurate, such as the explanation by Car and Driver. They say that power is how rapidly work is accomplished, while torque is the ability to perform work. In fact, mathematically, power equals torque multiplied by engine RPM. What Is Torque? Let's concentrate on what torque really is. Since our vehicles generate movement through rotation of the wheels, which in turn is accomplished via rotation of the engine's crankshaft, through the transmission, final drive, and differential, torque can be considered the ability to rotate. Published torque figures are typically manufacturer measurements done at the crank. Internal combustion engines may generate peak torque at low, mid, or high rpm operating ranges, or it may be a plateau from a defined rev range, as is the case with modern turbocharged engines. Diesel engines typically generate more torque than a similar displacement gas engine due to their longer stroke design and other considerations. The fact is, you need torque to move a vehicle, whether it's off-road or on-road. How much torque do you need? There's no magic number, really. You can't really say that vehicle X is better than vehicle Y based on X having more peak torque, as you have to look at other factors such as the rev band in which the peak torque is developed, the vehicle's curb weight, and more. Did you know that while internal combustion engines generate torque in a defined rev band or range that is above zero, electric motors generate peak torque at effectively zero rpm? The moment that an electric motor is just starting to rotate is the time it creates peak torque. At higher rpms, electric motors start to generate back EMF, and torque drops as a result. It's why even EVs with modest horsepower ratings are able to smartly step off the line and startle an internal combustion-engined car driver behind the wheel of an engine that's more potent on paper.  Low Vs High Torque The amount of peak torque is not only important, but at the RPM range at which it is generated. For example, naturally aspirated sports cars from the previous decades come with highly-strung engines that develop peak horsepower at over 7,500rpm (Ferrari and Lamborghini, to name a few manufacturers with this trait), and peak torque is also generated over 5,000rpm. While this makes them exciting to drive on the track, it affects their on-road controllability. If you've seen someone try to gently move one of these cars and promptly stall it, the reason is there's not enough torque at idle or just above idle to move it. You've got to rev the engine a bit to get it going. On the low-end torque spectrum, if you check out the specs of a larger displacement-engine off-roader, pickup truck or even a semi, you'll find the bulk of torque is concentrated low down in the rev range. In fact, if the vehicle is not loaded, you can quickly get it moving without touching the throttle pedal, as the torque available at idle is more than enough. This is the difference between low and high torque ranges.  Importance Of Torque in Off-Roading When you're off-roading, torque is critical as it's the ability to turn the wheels and get you out of trouble. Specifically, you want low-end torque as opposed to high-rpm torque. Why's that? Here are a few reasons. It gives you better control Low-end torque gives you better control as you don't need to excessively push your throttle pedal, allowing you to feather it and focus on handling the trail at a slower speed rather than having to maintain a higher than safe speed due to the higher rpm.  It helps your engine run cooler On the trails, you're going to be moving slowly, and if your engine is spinning at high rpm, apart from making a fair bit of noise, it's also going to generate heat that the cooling system may not be able to remove effectively due to the lack of airflow from forward motion that helps it along on the highway. Having ample torque available at lower rpm allows you to keep it cool.  Reduces engine wear Any engine spinning at high rpm, apart from generating heat, is also going to wear down quicker, especially in a high-load situation such as when you're trying to pull yourself out of the mud or climb a particularly steep hill. Check Out 4 Wheel Parts for Anything And Everything Off-Roading If you're looking for a comprehensive source to purchase anything and everything related to off-roading, with a broad array of high-quality products from established manufacturers, it's hard to beat what we at 4 Wheel Parts offer. We've established over 90 physical stores across the nation so there's bound to be one within a short drive from your home or office. If you're an online shopper, the 4Wheel Parts website allows you to browse our entire range, make purchases, and receive help and support from our friendly professional staff, much like you can expect when you visit one of our physical stores. We offer a price matching policy to ensure that you get maximum value, and should you shop with us online, we've got six distribution centers across the country to get your parts to your doorstep lickety-split. Choose 4 Wheel Parts for ultimate peace of mind. |
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