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      03-26-2008, 01:57 PM   #51
T Bone
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Quote:
Originally Posted by footie View Post
I am less impressed by this review, especially the jerk during upshifts. The whole reason of dual clutch is to be seamless in the changes, not noticeable and jerky like they were with SMG. Unless my understand of what the guy that wrote this is different I doubt I will like this that much.

I would also like to see performance figures for each of the different modes (Auto and Manual) to see if they effect the acceleration. If so then in my opinion BMW have f--ked things up BIG TIME.

Wow... Do you really believe what you write? The jerk on upshifts is a natural thing. When you have an engine at 8400 rpm and upshift, the next gear will bring down the RPMs by 1000-2000 rpms. This difference in RPMs must be absorbed by the transmission speeding up and the engine slowing down....

This translates into tire chirp on upshifts at redline.

If a meat computer can shift a manual transmission as quickly as MDCT, then it would also get the same chirp. But we know the mean computer is slow.

I will tell all of you guys this.... With SMG2, the E46 M3 didn't have enough power to really showcase the upshift tire chirp phenoma.... The M5 / M6's V10 with SMG3 does and it is a GLORIOUS sensation and not an annoyance.

With the E9x M3, it will have enough power to make this chirp....

Don't fear it, it is like a good thing.



Quote:
Originally Posted by swamp2 View Post
DCT WILL be worth about 20 hp and 20 ft lb (equivalently). The larger gear ratios AND shorter shift times will do this, period. If you do not disagree that the car will be measureably faster how can you disagree that there is not a significant and equivalent hp/tq gain? You've got this one wrong.

As far as the perception of gear changes it sounds like the system offers a full range of performance, barely noticeable changes in some modes, and noticeable not not nearly as noticeable as SMG in other modes. This does not mean much as all in terms of the performance advantages. All it really means is that I was a bit wrong about the particular design direction they took and whether or not super fast could be mixed with super smooth. That being said I always agreed with enigma that there is a certain amount of engine, flywheel and drivetrain inertia and that has to go somewhere.

The Cartest2000 simulations don't support significantly faster acceleration for the MDCT.....the reason the MDCT is faster is quicker shift times and not gear.

That is what the data says....let's see it on video
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