DCT on Track & Downshifting Problem

[Mickb]

Hi Guys

Did my breakin service just over a week ago and took the car out on track last Friday.

Meant to put a review up earlier but have been travelling from europe to mexico and have limited internet access so this will be brief.

Basically, I would give it a qualified "awesome", but the qualification is potentially a major one for some people.

Firstly, the car handles brilliantly and is incredibly balanced. For people more used to cars defaulting to understeer, this might make you feel its very tail happy but IMO its neutral, much more so than the E46. It is very easy to drift, and the Sport suspension setting is perfect for track work with very little body roll. I can understand where the ground control people are coming from on this one. I suspect many folks on this forum are going to ruin their car by changing springs and putting coilovers on it before even driving it in anger. I would urge anyone thinking of doing this to take the car out on track first. I never had such a blast at a track day before and by the end of the day was drifting the car at will. The very direct steering helps with this. I cant really understand the initial reviews on this: in sport the steering is very direct but very well weighted and it is easy to know what the front wheels are doing at all times. So for handling, I give the car an A+.

Next the more problematic review and I will choose my words carefully here, because I know the tendency of such forums to blow things out of all proportion. The gearbox. Firstly, upshifts. Truly amazing. As quick as you could possibly imagine. The delay that was reported on the net is a non-issue on track IMO. When you are full on the throttle, there is practically no delay in upshifting. I drove mainly in S5 and S6 and could tell no major difference between the two modes. Both are fantastic. I never once hit redline due to any supposed shift delay. I found the shift lights work really well, and while you are not staring at them, they are there at the corner of your eye and perfectly positioned. Shifts are so smooth compared to SMG its unreal. I had a go in a couple of E46 m3's between driving my own car and couldnt believe how jerky they were in comparison. A+ on upshifting.

Downshifting. er can I just leave now? I wil cut to the chase on this. The car will not always downshift for you under heavy braking. Its true. Initially I found it very frustrating. I got a friend with an E46 M3 SMG to drive my car to check I wasn't imagininig things and he found the same. Now just to verify: this is not the computer preventing a money shift; sometimes you will hit the down paddle when engine revs are less than 5k (so it should be no problem downshifting) and it would not do it. Now this does not occur every time and I found I hard to tell with any accuracy whether it was going to exhibit this behaviour. Sometimes the shifts were perfect with awesome rev matchng and in such circumstances it is a delight. The only conclusion I could draw at the end of the day, was that if the abs is triggered the car prevents dowshifting to avoid upsetting the cars balance. I can also say that for some reason, the only time this happened was going (or attemting to go) from 4th to 3rd. 3rd to 2nd was money every time. I should also point out that I had a full day on the track and towards the end of the day, I noticed this happeneing less and less, as if I subconsciously had adjusted to it, but without knowing why. Also, in the interests of balance, I must point out that in general the box worked exactly as you would want; amazing throttle blipping on downshifts and you can go up and down the box like a true sequential. This "problem" didnt in any way spoil my enjoyment of the day.

So in summary, I think this car has the potential to be a beast on track. THe balance & handling is awesome. It can either be a track day weapon or a drift god, depending on whether your idea of fun is shaving tenths of a second off your best lap or just having a laugh going sideways all day. The gearbox is amazing 95% of the time, but IMO still has some software issues to be ironed out.

Mick

[JEllis]

Originally Posted by Mickb

Hi Guys

Did my breakin service just over a week ago and took the car out on track last Friday.

Meant to put a review up earlier but have been travelling from europe to mexico and have limited internet access so this will be brief.

Basically, I would give it a qualified "awesome", but the qualification is potentially a major one for some people.

Firstly, the car handles brilliantly and is incredibly balanced. For people more used to cars defaulting to understeer, this might make you feel its very tail happy but IMO its neutral, much more so than the E46. It is very easy to drift, and the Sport suspension setting is perfect for track work with very little body roll. I can understand where the ground control people are coming from on this one. I suspect many folks on this forum are going to ruin their car by changing springs and putting coilovers on it before even driving it in anger. I would urge anyone thinking of doing this to take the car out on track first. I never had such a blast at a track day before and by the end of the day was drifting the car at will. The very direct steering helps with this. I cant really understand the initial reviews on this: in sport the steering is very direct but very well weighted and it is easy to know what the front wheels are doing at all times. So for handling, I give the car an A+.

Next the more problematic review and I will choose my words carefully here, because I know the tendency of such forums to blow things out of all proportion. The gearbox. Firstly, upshifts. Truly amazing. As quick as you could possibly imagine. The delay that was reported on the net is a non-issue on track IMO. When you are full on the throttle, there is practically no delay in upshifting. I drove mainly in S5 and S6 and could tell no major difference between the two modes. Both are fantastic. I never once hit redline due to any supposed shift delay. I found the shift lights work really well, and while you are not staring at them, they are there at the corner of your eye and perfectly positioned. Shifts are so smooth compared to SMG its unreal. I had a go in a couple of E46 m3's between driving my own car and couldnt believe how jerky they were in comparison. A+ on upshifting.

Downshifting. er can I just leave now? I wil cut to the chase on this. The car will not always downshift for you under heavy braking. Its true. Initially I found it very frustrating. I got a friend with an E46 M3 SMG to drive my car to check I wasn't imagininig things and he found the same. Now just to verify: this is not the computer preventing a money shift; sometimes you will hit the down paddle when engine revs are less than 5k (so it should be no problem downshifting) and it would not do it. Now this does not occur every time and I found I hard to tell with any accuracy whether it was going to exhibit this behaviour. Sometimes the shifts were perfect with awesome rev matchng and in such circumstances it is a delight. The only conclusion I could draw at the end of the day, was that if the abs is triggered the car prevents dowshifting to avoid upsetting the cars balance. I can also say that for some reason, the only time this happened was going (or attemting to go) from 4th to 3rd. 3rd to 2nd was money every time. I should also point out that I had a full day on the track and towards the end of the day, I noticed this happeneing less and less, as if I subconsciously had adjusted to it, but without knowing why. Also, in the interests of balance, I must point out that in general the box worked exactly as you would want; amazing throttle blipping on downshifts and you can go up and down the box like a true sequential. This "problem" didnt in any way spoil my enjoyment of the day.

So in summary, I think this car has the potential to be a beast on track. THe balance & handling is awesome. It can either be a track day weapon or a drift god, depending on whether your idea of fun is shaving tenths of a second off your best lap or just having a laugh going sideways all day. The gearbox is amazing 95% of the time, but IMO still has some software issues to be ironed out.

Mick

Good review...

When you downshifted were you sure to flick the paddle or is it possible that at times you held it for a few extra milli-seconds?

Jason

[M-Maika]

[mkoesel]

Originally Posted by Mickb

Downshifting. er can I just leave now? I wil cut to the chase on this. The car will not always downshift for you under heavy braking. Its true. Initially I found it very frustrating. I got a friend with an E46 M3 SMG to drive my car to check I wasn't imagininig things and he found the same. Now just to verify: this is not the computer preventing a money shift; sometimes you will hit the down paddle when engine revs are less than 5k (so it should be no problem downshifting) and it would not do it. Now this does not occur every time and I found I hard to tell with any accuracy whether it was going to exhibit this behaviour. Sometimes the shifts were perfect with awesome rev matchng and in such circumstances it is a delight. The only conclusion I could draw at the end of the day, was that if the abs is triggered the car prevents dowshifting to avoid upsetting the cars balance. I can also say that for some reason, the only time this happened was going (or attemting to go) from 4th to 3rd. 3rd to 2nd was money every time.

Thanks for posting. This has been reported here before - perhaps you saw the post and were adding some confirmation. The fact that it only happens in 4th to 3rd is new info I believe, at least new to me. It is unfortunate, but sounds firmly like it will be an issue only on the track. And furthermore it should be something that can be fixed with a software update.

Sounds like you had fun overall, reading your post makes me want the car even more.

[Mickb]

Originally Posted by JEllis

Good review...

When you downshifted were you sure to flick the paddle or is it possible that at times you held it for a few extra milli-seconds?

Jason

Yes, I am sure. I tried many different things and configurations and experimented with different braking styles etc. I also tried different downshifting styles; i.e. lets say I am at the end of the straight in 4th and have to come down the gears for a 2nd gear hairpin. I tried an initial 4th to 3rd shorty after beginning braking and again to 2nd. I also tried waiting until braking was nearly over and I am starting to ease off the pedal before trying a quick 4-3-2 downshift with 2 quick paddle flicks. Both styles would work sometimes and not others. My only conclusion is it is somehow ABS related.

Mick

[Mickb]

Originally Posted by mkoesel

Thanks for posting. This has been reported here before - perhaps you saw the post and were adding some confirmation. The fact that it only happens in 4th to 3rd is new info I believe, at least new to me. It is unfortunate, but sounds firmly like it will be an issue only on the track. And furthermore it should be something that can be fixed with a software update.

Sounds like you had fun overall, reading your post makes me want the car even more.

Yes, I thought I woudl add confirmation because there has been an awful lot of speculation and hearsay on these boards but precious little in the way of hard facts from owners of the cars who have driven hard on track. This is only my experience and my car of course and others may see differently.

As regards my 4th to 3rd speculation, it might be the particular track I drive on; the only situations where you have to brake really really hard happen to be the two straights which are 4th gear at the end. One of them also ends with a slight crest an dip which is a classic abs triggering situation which leads me to my theory that abs activation is the key to this. Where I was braking hard in 3rd and coming down to 2nd however, I never experienced the problem. Perhps it is velocity related as well.

Finally, you are correct on the fun part. This car is a blast, streets ahead of the E46 M3 and the 335i, and the track experience only vindicates my purchase decision.

Mick

[sayemthree]

I posted this problem about a month ago - you are not the first to experience this.

[footie]

It's interesting to hear that this occurred less and less as the day went on, is it you adjusting your driving style or the gearbox software learning your driving style in that situation?

[Mickb]

Originally Posted by sayemthree

I posted this problem about a month ago - you are not the first to experience this.

LOL I never said I was!!

[Mickb]

Originally Posted by footie

It's interesting to hear that this occurred less and less as the day went on, is it you adjusting your driving style or the gearbox software learning your driving style in that situation?

As I said above;

"....towards the end of the day, I noticed this happeneing less and less, as if I subconsciously had adjusted to it, but without knowing why"

You could be right, it might be adaptive, but I think I was probably a lot more controlled with my inputs and smooth in delivery which meant less abs triggering.

I am going to log this issue with my BMW dealer when I return home.

INcidentally, one final piece of info for people, I was driving with DSC fully off for most of the day, and MDM made no difference.

Mick

[GT3 Tim]

Originally Posted by Mickb

As I said above;

"....towards the end of the day, I noticed this happeneing less and less, as if I subconsciously had adjusted to it, but without knowing why"

You could be right, it might be adaptive, but I think I was probably a lot more controlled with my inputs and smooth in delivery which meant less abs triggering.

I am going to log this issue with my BMW dealer when I return home.

INcidentally, one final piece of info for people, I was driving with DSC fully off for most of the day, and MDM made no difference.

Mick

Thanks for all the good info Mick.

I should have my DCT Sedan on the 28th and will try to break her in quickly, then hit the track. I am curious to experience this myself and see if i can figure something out. Thanks again for the info....

[footie]

Originally Posted by Mickb

As I said above;

"....towards the end of the day, I noticed this happeneing less and less, as if I subconsciously had adjusted to it, but without knowing why"

You could be right, it might be adaptive, but I think I was probably a lot more controlled with my inputs and smooth in delivery which meant less abs triggering.

I am going to log this issue with my BMW dealer when I return home.

INcidentally, one final piece of info for people, I was driving with DSC fully off for most of the day, and MDM made no difference.

Mick

It was purely a thought, not a definite suggestion of what was happening. I still reckon it was more you adjusting your style and less the car, the opinion it's ABS dependent sounds valid because the same thing happens when cruise control is on, meaning it turns off if it activates.

I wonder it the GTR or other DCT cars are having similar issues or it is solely a M-DCT problem?

[!Xoible]

oh wow sounds like DCT sucks ass. sorry that you guys made the wrong choice.

[lucid]

Stop trolling around Mantis...

[lvwirelessguy]

It does suck. I would advise against buying one

[bmwwr250f]

This is part of the dct control units processing. it takes into account lateral, longitudinal acceleration sensors, engine speed, transmission gear selection, to determine if the downshift will cause uncontrolled load reversal. this could cause significant yaw control loss of the rear axle resulting in a spin out loss of control. the car was designed for the masses with varying degrees of driving skill, that may limit it when pushed to the extreme edge of performance for the true racer.

[Leonidas]

Originally Posted by lvwirelessguy

It does suck. I would advise against buying one

Care to elaborate why? Is it this downshifting issue or something else?

[enigma]

Originally Posted by Leonidas

Care to elaborate why? Is it this downshifting issue or something else?

He and Mantis are just trolling. Report the post and move on. The mods really need to crack down on this stuff.

[skierman64]

Originally Posted by enigma

He and Mantis are just trolling. Report the post and move on. The mods really need to crack down on this stuff.

Gearbox jealousy no doubt

[sayemthree]

IS it safe to buy the DCT yet? oops... that should be in the stupid ?? thread.

[sayemthree]

Originally Posted by Mickb

LOL I never said I was!!

LOL - I never said you said you said.....

I just want you to feel better "YOU ARE NOT ALONE!"

[lvwirelessguy]

Originally Posted by Leonidas

Care to elaborate why? Is it this downshifting issue or something else?

DCT is wonderful, I was just being sarcastic