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Listen to this video carefully - here's how to burn clutches up prematurely with 400HP. The guy fails to get the tires hooked up in 1st - result is he redlines in 1st way before he would if he were hooked up. As a result, the RPM drop when he shifts into 2nd takes him by surprise, and you can hear the clutch eat up all that excess energy as the engine slows down to where it should be.
 

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Greg, please explain. Because he has to shift so fast indicates he is spinning on the clutch disk and tires rather than maximizing pull. The tires have some grip so the clutch takes the beating. He would also be slower to accelerate, doing this.

But it looks good to the novice, right?


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Jim
00 M5 Titanium over Red
 

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Can anyone recommend an MOV->MPG converter, so I can hear this clip?

Last time I installed Apple QuickTime, my computer was hosed big time, and I don't plan to install it again.
 

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Keerist! I cringe everytime I hear this - what a wanker!! There ain't no way I'd let that twit drive my car...

BUT

Doesn't it sound beautiful??!!

Cheers
Andrew E
99 M5
 

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Jim Dolan - sorry for the late reply. I'm not sure I understand your question, though.

I'll try again, though, using different words. In my opinion the driver made two errors. His launch was initiated with RPM way too high, which resulted in excessive wheel spin all the way to redline. Because the wheels were spinning, the car was going a LOT slower in 1st at redline than it should have been if it were "hooked up".

And that lead to the second problem. In his 1-2 shift, you can hear the engine slow down OVER TIME to match the rather low revs of the now hooked up 2nd gear. Because the car wasn't going as fast as it should have been going if he redlined in 1st with the wheels hooked up, the rpm difference between 1 & 2 was a lot greater. A proper launch and 1-2 shift would have engaged the clutch much more quickly - you should hear the tires chirp, but you should hear the engine change pitch as if you went from one note to a lower one on a piano - more or less instant - instead of sliding from one to the other like a trombone. That is how clutches get ruined in a hurry.

I can't remember which of the magazines it was, but in one of the March '00 reviews, they said their optimum launch technique was to rev to only about 2000 RPM (if I remember correctly) and to "feed in" the throttle as the clutch pedal was lifted, specifically to AVOID excessive wheel spin.

/G
 

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Originally posted by greg:
Jim Dolan - sorry for the late reply. I'm not sure I understand your question, though.

I'll try again, though, using different words. In my opinion the driver made two errors. His launch was initiated with RPM way too high, which resulted in excessive wheel spin all the way to redline. Because the wheels were spinning, the car was going a LOT slower in 1st at redline than it should have been if it were "hooked up".

And that lead to the second problem. In his 1-2 shift, you can hear the engine slow down OVER TIME to match the rather low revs of the now hooked up 2nd gear. Because the car wasn't going as fast as it should have been going if he redlined in 1st with the wheels hooked up, the rpm difference between 1 & 2 was a lot greater. A proper launch and 1-2 shift would have engaged the clutch much more quickly - you should hear the tires chirp, but you should hear the engine change pitch as if you went from one note to a lower one on a piano - more or less instant - instead of sliding from one to the other like a trombone. That is how clutches get ruined in a hurry.

I can't remember which of the magazines it was, but in one of the March '00 reviews, they said their optimum launch technique was to rev to only about 2000 RPM (if I remember correctly) and to "feed in" the throttle as the clutch pedal was lifted, specifically to AVOID excessive wheel spin.

/G
Thanks Greg, we'll see you in Spartanburg.

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Jim
00 M5 Titanium over Red
 

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very informative discourse by obviously knowledgable discussants. In all fairness to the driver, do any of you think the gravel road contributed to the wheel spin or was all his technique?
 
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