Thread: S65 vs. S62
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      01-24-2013, 06:35 PM   #91
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Originally Posted by bruce.augenstein@comcast. View Post
Assuming he meant "flat torque curve", then I particularly want to know how that improves traction.
A flat torque curve (at a given throttle position, for simplicity's sake) means constant acceleration. The jerk (derivative of acceleration over time, da/dt) is 0.

A peaky torque curve will have non-zero jerk. Due to hysteris of the tire carcass, it can only tolerate so much jerk before the static coefficient of friction is overcome and the tires spin. While tires do have an outright torque maximum for given conditions, inducing enough jerk would be enough to spin tires that otherwise wouldn't from torque alone.

Example: If I apply 100% throttle in my supercharged S2000 from 2000 RPM to redline in 3rd gear, I won't break traction. If I punch it at 6k, I will. The amount of torque applied at 6k is no different. The jerk is.

Last edited by urBan_dK; 01-24-2013 at 06:41 PM.