Originally Posted by KrisZ
Originally Posted by ZeeOSix
Originally Posted by KrisZ
If torque by itself is not important, then why is it that most engine designs seek to have the torque curve as flat as possible? Ideally you don't want it to be a curve at all, but rather a nice flat horizontal line.
Because a flat torque curve will result in a nice linearly increasing HP curve. Flat torque curves are achieved by making the engine volumetric efficiency (VE) as high and as constant as possible over the RPM range.
Yes, that's correct. I posed the question to the person claiming torque by itself is not important.
Fact us that torque is the only thing we can measure, so the only way to know the power curve is to measure the torque curve. So it is essential to proper engine tuning.
Torque is measured if using a loaded dyno controlling the engine to a set acceleration rate. Horsepower is then calculated from the torque curve. An inertia dyno measures work (horsepower) by measuring how quickly the engine can accelerate a weighted drum. Torque is then calculated from the horsepower curve.
An old saying around the racing community is "Horsepower sells cars, but torque wins races" which comes from a lack of understanding. When you increase torque at any given rpm range, you also increase the horsepower in that range. The extra horsepower is what increases the acceleration rate through that range, not the torque.
Originally Posted by ZeeOSix
Originally Posted by KrisZ
If torque by itself is not important, then why is it that most engine designs seek to have the torque curve as flat as possible? Ideally you don't want it to be a curve at all, but rather a nice flat horizontal line.
Because a flat torque curve will result in a nice linearly increasing HP curve. Flat torque curves are achieved by making the engine volumetric efficiency (VE) as high and as constant as possible over the RPM range.
Yes, that's correct. I posed the question to the person claiming torque by itself is not important.
Fact us that torque is the only thing we can measure, so the only way to know the power curve is to measure the torque curve. So it is essential to proper engine tuning.
Torque is measured if using a loaded dyno controlling the engine to a set acceleration rate. Horsepower is then calculated from the torque curve. An inertia dyno measures work (horsepower) by measuring how quickly the engine can accelerate a weighted drum. Torque is then calculated from the horsepower curve.
An old saying around the racing community is "Horsepower sells cars, but torque wins races" which comes from a lack of understanding. When you increase torque at any given rpm range, you also increase the horsepower in that range. The extra horsepower is what increases the acceleration rate through that range, not the torque.