Shopping on line can be easy, simple and save you lots of money. It can also take a lot of your time, frustrate you, and result in unwanted purchases. Now the same can be said for regular high street shopping, but with the vast opportunity presented by the Internet it will pay you to spend a few minutes reading this and understanding how to better optimize your Power Band shopping experience:
1. Compare - without doubt the biggest advantage that the Power Band offers shoppers today is the ability to compare thousands of Power Band at a time. This is a great thing, but not necessarily all the time! Too much can be daunting at times so take advantage of the great comparison sites and where possible let them do the hard work for you.
2. Research - if it has been said it will be on the internet. Ignorance is no longer a justifiable reason for buying the wrong thing. Take the time to research in detail everything that you could possible want to know about
3. Testimonials - don't know anybody that has bought a Power Band? Wrong! If the Power Band is good the internet will let you know. Use the Internet as a friend and get testimonials before you buy.
4. Questions - Got a question about Power Band then search the Forums, FAQ's, Blogs etc. Don't be afraid to ask .....
5. Reputation - Never heard of the company selling Power Band? Don't worry, no reason why you should know every company in the world, but you know someone that does! Use the internet to find out what people are saying about Power Band and build up a picture of their reputation for sales, returns, customer service, delivery etc.
6. Returns - still worried that even after all of the above your Power Band wont be what you want? Check out the returns policy. There is so much competition now that someone, somewhere is bound to offer the terms that you are comfortable with.
7. Feedback - happy with your Power Band then let people know, after all you are depending on others people input in your buying decision, so why not give a little back.
8. Security - check for the yellow padlock on the Power Band site before you buy, and the s after http:/ /i.e. https:// = a secure site
9. Contact - got a question about Power Band, or want to leave a comment then check out the sites contact page. Reputable companies have them and respond.
10. Payment - ready to pay for your Power Band, then use your credit card or PayPal! Be aware of companies that don't accept them, there may be genuine reasons but given the huge amount of choice you have when buying online there is no reason at all not to buy via credit card or PayPal.
The
power band which refers to the range of operating speeds under which the engine is able to operate efficiently. A typical
gasoline automotive internal combustion engine is capable of operating at a speed of between around 750 and 6000 RPM, but the engine's power band would be more limited. The engine would typically not generate maximum
torque until higher operating speeds of perhaps 2500 RPM, after such, the torque drops off. The peak power (horsepower) might be closer to 5000 RPM. Such an engine would be said to have a "power band" of 2500-5000 RPM (another example would be from torque peak to
redline: 2500-6000 RPM).
This can be applied to any engine and establishes a reliable quantification of the above notion
"the engine is able to operate efficiently".
Power Band Tuning Considerations
The
engine tuning of the power band is a great challenge. It is possible to create a
peaky engine which generates more power from an engine if the manufacturer is willing to tune it for a very narrow power band. However, an engine with a narrow power band is more difficult to use. Such an engine must be coupled to a close-ratio transmission with many
gears in order to remain in its power band while providing an acceptably wide range of output speeds. A
flexible engine has a wide power band with less peak power, but could be tied to a less complex transmission (mechanics) with fewer gears and would not need to shift gears as often. Such an engine is also often called
torquey because it maintains a more constant level of torque over a wider range of RPM.
Cost and Usage Considerations
Sports cars and other performance vehicles are generally designed for peak power in a narrow power band. In these vehicles, the higher cost of a complex transmission would be more acceptable, and the driver could be assumed to be more willing to shift gears often to remain in the power band. These vehicles attempt to achieve the greatest possible power to weight ratio, and benefit greatly from using a smaller engine tuned for high peak power rather than a large engine with a wide power band. Trucks and full-size cars are more often tuned for a wide power band and use larger engines to achieve acceptable power over a wide range. These vehicles have the benefit of not having to shift as often as vehicles with a narrow power band.
Tuning for high Horsepower Output or high Torque Output?
Since automobile shoppers rely heavily on the peak Power (physics) output figure (typically given in horsepower or kilowatts), some auto makers tend towards producing "peaky" engines. For example,
Honda's 2006 Honda Civic Si's K20Z3 engine generates 197 hp (147 kW) at 7800 RPM. Though it produces a fairly flat torque curve compared to many engines, it only produces 139 ft·lbf (188 N·m) and it has relatively sharp (or "peaky") power delivery, this requires the driver to keep the engine at high RPM to extract the best performance from the Honda Civic. In contrast, Volkswagen's 2006 Volkswagen GTI's 2.0T engine produces about 200 hp (149 kW) from 5,100 RPM to 6,000 RPM and a relatively flat torque band of 207 ft·lbf (281 N·m) from 1,800 to 5,000 RPM. This wide power delivery makes it easier for the driver to extract the vehicles best performance.
Power band considerations with a
Continuously variable transmission vehicle
Because a
Continuously variable transmission vehicle has the capability of keeping RPMs within the crest of the power band under acceleration, a peaky engine is optimal. Under full acceleration 100% of the available power can be extracted at all times. There is no shifting, and no moving out of the power band. This type of transmission is more efficient than others due to power band issues mentioned previously, but is not favored by many due to the lack of apparent power. Drivers are accustomed to the sudden lurch off the line and the shifting of the transmission. Though these are only actions of less efficient transmission, some vehicle manufacturers have computerized such events in to the transmission to add to the perception of power and torque.
Non-Automotive Power Band Tuning
Engines for
ships and
aircraft are also generally designed with a narrow power band as these vehicles do not have to operate over a wide speed range. They instead reach their optimal operating speed and remain there for the duration of their trips. As a result, they benefit from tuning for peak power and efficiency in a narrow power band.
See also
Online Resources
Dyno Results
The
power band which refers to the range of operating speeds under which the engine is able to operate efficiently. A typical gasoline automotive internal combustion engine is capable of operating at a speed of between around 750 and 6000
RPM, but the engine's power band would be more limited. The engine would typically not generate maximum
torque until higher operating speeds of perhaps 2500 RPM, after such, the torque drops off. The peak power (
horsepower) might be closer to 5000 RPM. Such an engine would be said to have a "power band" of 2500-5000 RPM (another example would be from torque peak to
redline: 2500-6000 RPM).
This can be applied to any engine and establishes a reliable quantification of the above notion
"the engine is able to operate efficiently".
Power Band Tuning Considerations
The
engine tuning of the power band is a great challenge. It is possible to create a
peaky engine which generates more power from an engine if the manufacturer is willing to tune it for a very narrow power band. However, an engine with a narrow power band is more difficult to use. Such an engine must be coupled to a close-ratio transmission with many gears in order to remain in its power band while providing an acceptably wide range of output speeds. A
flexible engine has a wide power band with less peak power, but could be tied to a less complex transmission (mechanics) with fewer gears and would not need to shift gears as often. Such an engine is also often called
torquey because it maintains a more constant level of torque over a wider range of RPM.
Cost and Usage Considerations
Sports cars and other performance vehicles are generally designed for peak power in a narrow power band. In these vehicles, the higher cost of a complex transmission would be more acceptable, and the driver could be assumed to be more willing to shift gears often to remain in the power band. These vehicles attempt to achieve the greatest possible power to weight ratio, and benefit greatly from using a smaller engine tuned for high peak power rather than a large engine with a wide power band. Trucks and full-size cars are more often tuned for a wide power band and use larger engines to achieve acceptable power over a wide range. These vehicles have the benefit of not having to shift as often as vehicles with a narrow power band.
Tuning for high Horsepower Output or high Torque Output?
Since automobile shoppers rely heavily on the peak Power (physics) output figure (typically given in horsepower or
kilowatts), some auto makers tend towards producing "peaky" engines. For example, Honda's 2006 Honda Civic Si's K20Z3 engine generates 197 hp (147 kW) at 7800 RPM. Though it produces a fairly flat torque curve compared to many engines, it only produces 139 ft·lbf (188 N·m) and it has relatively sharp (or "peaky") power delivery, this requires the driver to keep the engine at high RPM to extract the best performance from the Honda Civic. In contrast,
Volkswagen's 2006 Volkswagen GTI's 2.0T engine produces about 200 hp (149 kW) from 5,100 RPM to 6,000 RPM and a relatively flat torque band of 207 ft·lbf (281 N·m) from 1,800 to 5,000 RPM. This wide power delivery makes it easier for the driver to extract the vehicles best performance.
Power band considerations with a
Continuously variable transmission vehicle
Because a
Continuously variable transmission vehicle has the capability of keeping RPMs within the crest of the power band under acceleration, a peaky engine is optimal. Under full acceleration 100% of the available power can be extracted at all times. There is no shifting, and no moving out of the power band. This type of transmission is more efficient than others due to power band issues mentioned previously, but is not favored by many due to the lack of apparent power. Drivers are accustomed to the sudden lurch off the line and the shifting of the transmission. Though these are only actions of less efficient transmission, some vehicle manufacturers have computerized such events in to the transmission to add to the perception of power and torque.
Non-Automotive Power Band Tuning
Engines for ships and aircraft are also generally designed with a narrow power band as these vehicles do not have to operate over a wide speed range. They instead reach their optimal operating speed and remain there for the duration of their trips. As a result, they benefit from tuning for peak power and efficiency in a narrow power band.
See also
Online Resources
Dyno Results
