[BEE35i]

Can anyone shine some light on whether they share identical ZF gearboxes?

I have read that they are the same hardware with different software but cannot confirm the truth behind this.

[_ink]

lots of speculation, apparently mechatronics are also different.

M3 DCT's also have their own dedicated TCU controlling the DCT which is attached directly to the DCT unit.

Why the interest young Jedi?

[BEE35i]

Thanks Ink,

I just noticed they handle a lot of abuse as people drift/powerslide on them with the torque of a v8 behind it.

As you would know its TQ which kills clutches not HP, so I wanted to know if they run the same trans and clutch plates etc which would put my mind at ease when I give my DCT a hard time.

[ATTN]

Originally Posted by BEE35i

Thanks Ink,

I just noticed they handle a lot of abuse as people drift/powerslide on them with the torque of a v8 behind it.

As you would know its TQ which kills clutches not HP, so I wanted to know if they run the same trans and clutch plates etc which would put my mind at ease when I give my DCT a hard time.

hello young blood, why don't you get a m3?

[BEE35i]

Hi ATTN,

Funny you should say that, I was thinking about buying one which was another reason I started the topic.

Manual or DCT would be the next thing to decide.

[DR-JEKL]

Definately the same gearbox, albeit the M has a unique software calibration AFAIK.

I would have thought a FBO N54 would put out a lot more torque than the S65. The S65 sound great and rev much harder albeit the lack of torque can make the M3 not feel all that fast

[Stuart@BMRAutowerkes]

DCT M3 for sure purely for the downshifts.

If M3 and 335 DCT are the same then the M3 GTS gearbox tune may be of interest to the DCT guys.

[ATTN]

Originally Posted by Stuart@BMRAutowerkes

DCT M3 for sure purely for the downshifts.

If M3 and 335 DCT are the same then the M3 GTS gearbox tune may be of interest to the DCT guys.

Please elaborate on this M3 GTS gearbox tune. Is this similar to Alpina flash?

[_ink]

Originally Posted by BEE35i

Thanks Ink,

I just noticed they handle a lot of abuse as people drift/powerslide on them with the torque of a v8 behind it.

As you would know its TQ which kills clutches not HP, so I wanted to know if they run the same trans and clutch plates etc which would put my mind at ease when I give my DCT a hard time.

Clutch plates are exactly the same, which you can verify with the plates working across platform when upgrading to say the SSP ones: http://www.sspperformance.com/bmw-dc...h-package.html

Here is a good technical thread on the DCT, check out the PDF attached in the thread: http://www.e90post.com/forums/showthread.php?t=747010

[CYL]

hi, just want to ask for an automatic vehicle, would downshift damage the gearbox?
I read a lots of article on the internet and some said it wont, some said it will....

with my 325i, should I downshift? if not, what's the real purpose of the +/- as well as the paddles....

[AUSf22]

Originally Posted by CYL

hi, just want to ask for an automatic vehicle, would downshift damage the gearbox?
I read a lots of article on the internet and some said it wont, some said it will....

with my 325i, should I downshift? if not, what's the real purpose of the +/- as well as the paddles....

No it won't damage your gearbox.. even if you're driving in D the gearbox downshifts for you, so you will downshift whether you like it or not. The purpose of your +/- is you can choose when those downshifts or upshifts occur at the RPM you desire...

[CYL]

Originally Posted by AUSf22

No it won't damage your gearbox.. even if you're driving in D the gearbox downshifts for you, so you will downshift whether you like it or not. The purpose of your +/- is you can choose when those downshifts or upshifts occur at the RPM you desire...

thanks, but there are some articles saying that it damages the transmission.
let's say when it's 70km/h, taking the corner, and you downshift it from 6 to 3 or 4, the rpm will increase for use, with that suddenly change in rpm, it feels like the statement saying that it damages the transmission is likely?

I don't do downshift often (99% of the time I use D) but I am just interested in this topic suddenly.

[AUSf22]

Originally Posted by CYL

thanks, but there are some articles saying that it damages the transmission.
let's say when it's 70km/h, taking the corner, and you downshift it from 6 to 3 or 4, the rpm will increase for use, with that suddenly change in rpm, it feels like the statement saying that it damages the transmission is likely?

I don't do downshift often (99% of the time I use D) but I am just interested in this topic suddenly.

Most likely for manual cars if you downshift incorrectly (eg 5th to 2nd) and other instances where you don't rev-match. The gearbox you have in your 325i won't allow you to downshift when it thinks you are harming the gearbox. Don't worry about damaging your gearbox, slap it down a gear when you feel like overtaking

[Socket]

More likely to damage it doing wheel spins correct?

[JB4-335]

Same Getrag gearbox different software.

Stock clutch plates can hold quite a bit of torque if tuned correctly. Increasing the clamping pressure can work well but having your load to torque tables set up right is only part of the equation.

[Stuart@BMRAutowerkes]

Originally Posted by ATTN

Please elaborate on this M3 GTS gearbox tune. Is this similar to Alpina flash?

GTS gearbox tune advantages:
- faster shifting in higher drivelogic modes (probably only applicable to M3s though?)
- smoother shifting under partial throttle
- smoother downshifts when coming to a stop
- less lag when engaging reverse

Overall it makes it more comfortable and the logic of the transmission is improved. Although the DCT in 335s seems to behave better than in the M3, so M3 owners may notice more of an improvement.

[BEE35i]

Excellent info guys! Stu I agree with your statement on downshifts! Amazing noise with an ipe!

[BEE35i]

On the same note, any workshops in AUS completed any DCT clutch upgrades?

[_ink]

Originally Posted by BEE35i

On the same note, any workshops in AUS completed any DCT clutch upgrades?

Now that's a solid question! I've been researching myself and haven't found any!

[XIX]

Originally Posted by BEE35i

Thanks Ink,

I just noticed they handle a lot of abuse as people drift/powerslide on them with the torque of a v8 behind it.

As you would know its TQ which kills clutches not HP, so I wanted to know if they run the same trans and clutch plates etc which would put my mind at ease when I give my DCT a hard time.

M3 and 335i have similar torque stock. A tuned 335i (n54) will have considerably more (+30%) so the fact the M3 shares the same gearbox wont be much help. The M3 also doesnt bring in its torque til much later, so it will be much easier on the gearbox, whereas the n54 will shock it quite early in the range.

Forced induction will always give you more torque (and power) and always alot earlier. That is why it is so much more popular now ...

[I CU2]

How reliable is the 335i/M3 DCT?