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Old 07-22-2018, 09:45 AM   #41 (permalink)
stefanv
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2001 Saturn - '01 Saturn SL1
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Quote:
Originally Posted by oldtamiyaphile View Post
You can try this (in someone else's car of course). Sit on a hill, hold the car on the clutch at idle. Increase RPM. The car doesn't move because regardless of RPM, you're only transferring the same number of newtons.
Yes, you're transferring the same number of Newtons (force), but you're expending more power while producing those Newtons (thus, less efficiently). That extra power has to go somewhere. Since it isn't going into making the car move, it is going into removing material from the clutch and making it hotter.

Slip time and RPM is what wears out a clutch. It's just like if I'm sanding a piece of wood. If I apply the same amount of force, but sand faster, I will remove wood faster. If this weren't the case, power sanders would be pointless, since you could just make one firm but slow pass with a piece of sandpaper and achieve the same result.

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Stefan Vorkoetter: Programmer, hobbyist, amateur watchmaker, pilot, and collector of fountain pens, slide rules, calculators, and watches.

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