35is DCT

[is300wrx]

Is the DCT found in the 35is same as the ones in the e9x M3?

[morfinx]

Originally Posted by is300wrx

Is the DCT found in the 35is same as the ones in the e9x M3?

I don't think so. It's very similar but not the exactly same. For one, the DCT in the Z4 won't hold a redline even if you are in manual mode. It will just upshift.

[is300wrx]

Originally Posted by morfinx

I don't think so. It's very similar but not the exactly same. For one, the DCT in the Z4 won't hold a redline even if you are in manual mode. It will just upshift.

That's really too bad. So if you have the pedal floored, regardless of whether you're in S mode, it'll act like its in D mode by up shifting at red line.

Wish the 35is gave you the option for the 6 speed manual.

[mpbruin108]

Originally Posted by is300wrx

That's really too bad. So if you have the pedal floored, regardless of whether you're in S mode, it'll act like its in D mode by up shifting at red line.

Wish the 35is gave you the option for the 6 speed manual.

Having owned a DCT E92 M and a 35i Z (not IS), it seems to be just as fast but the paddle shifters are definitely different. However, the M does have M Mode and the Z doesn't so I would think the gearing and programming would be different for those different situations but what do I know.

Hmm..I wanted to chime in but I guess I wasn't too helpful. haha

[Asbjorn]

Originally Posted by morfinx

I don't think so. It's very similar but not the exactly same. For one, the DCT in the Z4 won't hold a redline even if you are in manual mode. It will just upshift.

Right, and that is just software. The M cars also come with more options for gear shifting speeds and perhaps launch control rpm. It simply means that we cannot abuse our Getrag DCT boxes (an engines) in the same way that M car, or for that matter, Farrari owners can. It doesn't mean that the hardware cannot be asked to do it...

Before I bought this car I thought I would miss these features. And I still think its like having installed 10GB of RAM in a PC, but then the OS can only figure out how to access 2 of them. But that was also when I thought I would be spending most of my time on a track drifting around...

Now I know the only option I am missing is to be able to select a slower shifting speed while in Manual mode. I would have liked to be able to shift manually and at the same time be the most gentle to the clutches.

If you are the type of person who thinks not being able to head-bang the red-line is a big deal, don't get an E89, not even a manual one... get something which is cheaper to repair and maintain.

[Asbjorn]

Originally Posted by is300wrx

That's really too bad. So if you have the pedal floored, regardless of whether you're in S mode, it'll act like its in D mode by up shifting at red line.

Wish the 35is gave you the option for the 6 speed manual.

M mode and S mode is not the same! And D mode will never go to the red-line at all.

With S mode, combined with sport+ and ESS stg 2, I two times experienced mine upshifting two gears instead of just one (due to excess wheelspin during shifting)! Even with the pedal floored, S mode shifts gears at lower RPMs (for instance 6.5K instead of 7K) where there is more torque available.

I believe M mode is the only mode which will take you to red-line. And then it up-shifts automatically...

[z4z4z4]

~6100 rpm is where whp is max. Hitting redline is not a desire, it is user error.

[ManiacGT]

Agreed. Redline on the N54 is a bad idea, power drops off dramatically after 6000 rpm. Just drive it and find out. It bugs me no end that kick down revs way past where usable power ends, you can feel the thump in your back as the turbos, at full tilt, are then used for the next gear change. If you want maximum acceleration, its sport mode, manual DCT shifting and make sure you change up very shortly after 6000rpm each time.

[is300wrx]

Thanks for all the replies.

I currently have an e92 with DCT and I might be looking to add on a Z4 35is in the near future. Having owned a 2004 z4 3.0 6 speed in the past, I know how much fun and exciting these cars can be.

I just wanted to find out how different the DCT would act in the Z4 since the DCT in the M is amazing!

[jparnes1]

DCT in M cars are a "truer" manual than DCT in Z4's. M car trannies have a neutral position, for one thing. In the Z4, if you take your foot off the brake at a standstill, you will idle forward, hence, no neutral.

[Alext]

Unless you are going to track the car, then the DCT is amazing on street. I think 99% of owners will fall into the 'street' category.

[is300wrx]

Originally Posted by jparnes1

DCT in M cars are a "truer" manual than DCT in Z4's. M car trannies have a neutral position, for one thing. In the Z4, if you take your foot off the brake at a standstill, you will idle forward, hence, no neutral.

Will it rev match when you downshift, creating an intoxicating yet addicting sound from the engine?

[jparnes1]

Originally Posted by is300wrx

Will it rev match when you downshift, creating an intoxicating yet addicting sound from the engine?

Yes, it's an automatic, computer-controlled transmission so it rev matches. You'd be pretty much screwed if it didn't.

[flpnout]

Originally Posted by ManiacGT

Agreed. Redline on the N54 is a bad idea, power drops off dramatically after 6000 rpm. Just drive it and find out. It bugs me no end that kick down revs way past where usable power ends, you can feel the thump in your back as the turbos, at full tilt, are then used for the next gear change. If you want maximum acceleration, its sport mode, manual DCT shifting and make sure you change up very shortly after 6000rpm each time.

I agree, even being Dinan tuned, I need to shift between 6k to 6200 RPM, right before the power band drops.

[javol]

Originally Posted by is300wrx

Will it rev match when you downshift, creating an intoxicating yet addicting sound from the engine?

The Z4 DCT does match revs and is a fast and very good auto. But the upshifting and the downshifting aren't comparable to the M3 DKG with Drivelogic. The M3 DKG manual upshifts are faster and more "brutal" than the Z4 ones and the dowshifts are faster and more involving too. For example the M3 can drop from 6º to 3º in 1 sec more or less, simply tapping three times in a very rapid sequence. And you CAN HEAR EVERY SINGLE GEAR downshifted (a sort of zum-zum-zum !). In the Z4 you can NOT hear it so clearly. All this is due to a better software in the M3 DKG, to the fantastic intake sound of the V8 and to its natural attitude to rev high.

[nicknaz]

The DCT in the Z4 is lazy on downshifts (particularly when in a corner), even in sport+ / manual mode (compared to other dual clutch gearboxes like Porsche PDK). I agree with other posters that the M gearbox has much better software for sport driving.

That said, it I think the DCT is a great gearbox (much better than traditional slushbox) and shifts more cleanly / consistently than I could with a manual (my car is DCT).

[SgtGigglebox]

Originally Posted by nicknaz

The DCT in the Z4 is lazy on downshifts (particularly when in a corner), even in sport+ / manual mode (compared to other dual clutch gearboxes like Porsche PDK). I agree with other posters that the M gearbox has much better software for sport driving.

I found myself annoyed by this just this week. It had been several days since I had it out and the damn thing wanted to cling to the higher gears. Even after I switched to the paddles it still seemed to take every chance it could to upshift (after not touching it for some amount of time, etc.)

[morfinx]

Originally Posted by Gigglebox

Even after I switched to the paddles it still seemed to take every chance it could to upshift (after not touching it for some amount of time, etc.)

I'm confused as to what you mean here In manual mode it should never upshift unless you hit redline?

[javol]

Originally Posted by Gigglebox

I found myself annoyed by this just this week. It had been several days since I had it out and the damn thing wanted to cling to the higher gears. Even after I switched to the paddles it still seemed to take every chance it could to upshift (after not touching it for some amount of time, etc.)

If you tap the paddles when in D, the car shifts manually for some seconds then came back to "a normal auto D" if you not insist with the paddles.
For a full manual you have to move the shifter to the left (S position) then start to use the paddles or to move the shifter forward - backward.
When fully manual the gears are labelled by an "M": M1, M2, etc. on the central display.

[teagueAMX]

Originally Posted by morfinx

I'm confused as to what you mean here In manual mode it should never upshift unless you hit redline?

Originally Posted by javol

If you tap the paddles when in D, the car shifts manually for some seconds then came back to "a normal auto D" if you not insist with the paddles.
For a full manual you have to move the shifter to the left (S position) then start to use the paddles or to move the shifter forward - backward.
When fully manual the gears are labelled by an "M": M1, M2, etc. on the central display.

@ morfinx to amplify just a bit on javol's post, the term "manual" mode is a bit of a misnomer in a DCT equiped car. Regardless of make, model etc. you really aren't in total control. The exception would be a few of the high end supercars which allow the driver "more" control.

It's sort of like "fly by wire" in a jet - you move the control stick but a computer is actuating vertical and horizontal control surfaces based on millions of data calculations per second. Likewise with a DCT, in some situations the computer just won't let you shift down a gear (e.g., what the computer perceives may damage your drive train), and as mentioned sometime it will upshift without your permission - even in full "manual" mode. In both cases, the DCT (e.g., computer control gear box) is following some higher directives hard coded into the ECU by BMW.

[wdlfbio]

Originally Posted by Alext

Unless you are going to track the car, then the DCT is amazing on street. I think 99% of owners will fall into the 'street' category.

Got the 2012 35is, then sold the '08 E92 M3 with DCT.

The downshift in the 35is sounds better than the M3 and I totally agree that it's a driver error to redline the E89. Way past the power gain at that point. The Z does not handle as well as the M, but I can't say I noticed any difference in the shifting.

[ZheHbKa]

Originally Posted by is300wrx

That's really too bad. So if you have the pedal floored, regardless of whether you're in S mode, it'll act like its in D mode by up shifting at red line.

Wish the 35is gave you the option for the 6 speed manual.

+1