SLK/R171: optimum launch: Manual SLK drivers help
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Joined: Mar 2004
Posts: 58
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From: Los Angeles, CA
'05 SLK350
optimum launch: Manual SLK drivers help
Was wondering if any of you know the optimum RPM at which to drop the clutch to produce the best acceleration. I've had no luck trying to launch this car so far.
If I rev at 3500 RPM and drop the clutch, the car peels out and burns all of 1st gear...I don't start going anywhere until I shift to 2nd. If I drop it at around 2500 rpm the car almost stalls...
Have any of you tried launching? Any luck? Whats the optimum RPM? If no one had any luck then I guess this car is just not meant to be launched...
If I rev at 3500 RPM and drop the clutch, the car peels out and burns all of 1st gear...I don't start going anywhere until I shift to 2nd. If I drop it at around 2500 rpm the car almost stalls...
Have any of you tried launching? Any luck? Whats the optimum RPM? If no one had any luck then I guess this car is just not meant to be launched...
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Joined: May 2005
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From: Pasadena, CA
'12 C204 C250, '05 SLK350 (sold)
I usually launch around 3500-4000 and feather the clutch a bit to avoid wheelspin when I'm serious about beating someone off the line. Since 1st gear is very short, there's obviously way too much torque for the tires to handle if you drop the clutch. I'd practice using medium to hard feathering of the clutch to complement your personal driving style. If you have aftermarket wheels with good 265 width tires, you could probably use less feathering.
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Joined: Sep 2004
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From: Colorado, USA
MBZ SLK
Originally Posted by dwei42
slktyperice:
Can you please elaborate what you mean by feathering the clutch?
I'm not familiar with the term.
Thanks!
Can you please elaborate what you mean by feathering the clutch?
I'm not familiar with the term.
Thanks!
Member
Joined: May 2005
Posts: 247
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From: Pasadena, CA
'12 C204 C250, '05 SLK350 (sold)
Originally Posted by Ynot
Quick and simple answer: Feathering is letting go of of the clutch slowly as opposed to dumping the clutch, letting go completely, feathering allow your tires to grip. Dumping would cause it to burn-out, no grip as you've mentioned. Up here in altitude where we lose up to 30% horsepower, dumping the clutch at 2900 rpm seems to work fine. YMMV
Yes, feathering the clutch is holding it in the middle between fully gripping and off. It's quite an art, you'll have to practice it a lot. I'm sure you subconsciously do it when you're stopped uphill on a steep hill and you're not pressing on the brake.
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Joined: Sep 2004
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From: Colorado, USA
MBZ SLK
Originally Posted by slktyperice
Losing that much hp, that means any Forced Induction solution would do wonders up in Colorado. You could almost double the boost of the Kleeman SC and still not blow your engine/transmission since it's producing less HP at the crank while bone stock.
