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I'll be taking my Beast to Infineon Raceway later today to run it down the dragstrip. I know to turn the DSC off, but my main concern is getting a good solid launch and a decent 60ft time, without damaging the tranny. Is this possible? At what RPM is it optimum to launch the M5 at and how should I let the clutch out? Just dump it or feather it out? Any tips would be appreciated, hope I can represent for the M5's in a good way at the track tomorrow. :M5launch:
 

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wow, i've been wanting to do this for a while. Next time we should try to get a group to go.
My advise (not necessarily worht much, since i've not done this for years) would be to roll out at around 1600-1800 rpm, slipping the clutch, once you've got the clutch out see how much throttle you can give in first.
 

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The rpm you want to hold prior to launching will depend on your tires and the available traction too. Somewhere between 1600-2200 is most likely the sweet spot. If your tires are relatively fresh (not too many heat cycles on them, i.e. not a couple of years old or 15k+ miles), you should be able to launch ~2000rpm. Try to quickly find that balance point between throttle application and clutch engagement.

You will need to feather the clutch for just a bit as you add throttle -- that's the tricky balance point since you are balancing the amount of tire spin (just a tad is probably perfect) versus slipping the clutch while adding power. The later must be done with care else you risk overheating the disc -- just make sure to never let anything near full power go through a clutch that is not totally hooked up. It is possible to get the clutch and tire hookup just "right" and rocket out of the hole in the M5. All of this depends on track conditions too of course.

If you’re idling through a long line to the starting line, try to do so with your hood open as much as possible to limit the amount of heat soak (which will kill your times since it will have the engine running rich and with retarded timing by the time you get to the line).

Good luck,
Chuck
 
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