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      03-26-2008, 07:42 PM   #80
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swamp2's Avatar

Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

iTrader: (1)

Originally Posted by enigma View Post
You clearly have no understanding of phyisics. It would be great if I could stop from 100mph in without a jerk also, but thats equally problematic.

Where do you think the energy of fast spinning engine goes? Options are

1: Quickly to the rear tires producing a jolt of extra acceleration
2: Gradually to the rear tires while reducing engine output to allow the engine to slow without extra acceleration.

#1 = S6
#2 = S1

And you have 4 other choices between them to suite the drivers taste. This is why people buy BMW and not the "one size fits all" audi solution. There will be a performance difference. Its unavoidable.
Footie, there is another effect here. This engine under WOT at redline produces about 250 ft lb. Shifting when getting on it drops the rpm to something like 6000 (of course this varies gear by gear and on gas pedal depression as well). Around that 6k rpm the engine is producing very close it its peak torque, 300 ft lb. Aren't you going to feel a jerk when you try to apply 20 more ft lb over a very short time interval? Unless you make a careful effort to hide it you are going to feel it. You can play tricks with DCT and all sort of parameters as I have mentioned many times in the past like spark, timing, fuel flow, automated throttle control, clutch times and clutch phasing, etc. to control the jerkiness. As long as the jerk is not fake, which I highly doubt it is, I suspect that even with DCT more performance requires more jerk. But in all cases the jerk is less than SMG because there is almost no deceleration. My innacuracy in the past may have been believing that BMW could provide the most performance with little to no jerk. I do think I was wrong about the subtlety myself.