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Discussion Starter #1
Does anyone here know how launch control is programmed? Does it have a set program for all instances or does it limit power and slip the clutch based on what's happening at that instant? I'm just curious if the hydraulics are fast enough to constantly alter pressure in those few hundredths of a second when the car is just getting off the line, and if it can't do so and has a set prgram, then how does it work, or does it work, over a wide variety of surfaces and tractions? It just seems a set program would only be perferct on the preprogrammed traction surface.

Regarding SMGIII, isn't this one the first one with a double plate clutch? I'm curious about this one too, as this would vastly improve reliability and smoothness of the car as it can hadle slippage much better.

Thanks in advance for the always well-informed responses.
 

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HaveVR6wantM5 said:
Does anyone here know how launch control is programmed? Does it have a set program for all instances or does it limit power and slip the clutch based on what's happening at that instant? I'm just curious if the hydraulics are fast enough to constantly alter pressure in those few hundredths of a second when the car is just getting off the line, and if it can't do so and has a set prgram, then how does it work, or does it work, over a wide variety of surfaces and tractions? It just seems a set program would only be perferct on the preprogrammed traction surface.

Regarding SMGIII, isn't this one the first one with a double plate clutch? I'm curious about this one too, as this would vastly improve reliability and smoothness of the car as it can hadle slippage much better.

Thanks in advance for the always well-informed responses.
I don't know how well informed this is, but I believe that M Diff handles the slippage issue, and the clutch is a single plate configuration. At least as I understand the question.

?????? simmikie
 

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Very interesting question. What I have read so far, the LC had troubles to work properly in cold&wet. Autocar got very unsatisfactory 0-100 kph results with LC.
However, there was also some material from BMW where they actually did LC start on salt lake... Don't know whether it was just a marketing bullshit or serious informaion
 

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I imagine that the system is tied into the ABS wheel sensors to determine wheel speed, and from that the amount of wheel spin at the rear, combined with RPMs, throttle position, and possibly even some form of acceleration measurement (as in G force) to find the optimum clutch pressure, etc.
 

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Discussion Starter #6
Thanks for the replies. Some querstions have been cleared up but others still vague. When i said double clucth I meant double plate clutch not the Audi DSG dual clutch setup. I remember reading that the 7 speed transmission was built from scratch and used this sort of clutch setup as opposed to the previous SMGs which were adapted from normal manual six speeds.
 

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The car we tested the other week, performed exceptionally well during LC.

David
 

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DavidS said:
The car we tested the other week, performed exceptionally well during LC.

David
Very well indeed - I was hooked :biggrin:
 
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