Quote:
Originally Posted by Nick2016M2
I've just read through this full thread and tried to follow along with the log graphs posted. I 100% agree that there is an artificial lag induced by the ECU when you don't shift at redline. I too have been playing around with driving styles since I got this car 4 years ago and it is my single biggest disappointment with this car.
Shifting quickly at a 5500 RPM shift gives the clunky-ness associated with the rev-hang. A slightly longer shift can be smoother, but in either case there is a huge lag when getting back on the throttle. More than just turbo-lag, which can be measured by simply going to 0% throttle and then back to 100% in the same gear.
Thinking it was safety (traction) related, I've tried DSC OFF and it performs the same way. I, too, am convinced the lag is to protect the drivetrain.
The only way I've experienced no lag is a quick shift at redline with DSC off. It's to the point that I don't enjoy daily driving the car and have considered an E36 or E46 for more daily enjoyment (both of which I've owned before).
I applaud all of the work Nezil has done here and it is the first thread that really tries to use data to get to the root of the problem. If a fix is discovered I am on board.
One question though - If SeanWRT suggests that the lag may be introduced on the 6MT to prevent overboost because of turbine speed and a drop engine RPM, how does the ECU on a DCT live with that with instantaneous changes in engine RPM? Seems that would only make it worse..?
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DCT shifts are so quick it doesn't need to bleed off boost like with manual. No drop = no overboost.