Thread: S65 vs. S62
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      01-24-2013, 11:11 PM   #94

Drives: 05 M3, 95 M3 euro, 01 M5, e91
Join Date: Apr 2008
Location: West Chester, PA

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Originally Posted by urBan_dK View Post
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.
The S62 has a pretty kickass torque curve.

S62 vs s85, stock vs stock:


Current Cars: 2005 IR/IR M3, 2001 LMB/blk M5, Wife's e91, 1995 S50 B32 GT3 RS Green M3 Race Car
Former Cars: 2004 TiAg/IR M3, 1996 TV/black M3, 1995 AW M3 shell
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