BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read
M2 Technical Topics > Track / Autocross / Dragstrip > DCT behavior at autocross

Post Reply
 
Thread Tools Search this Thread
      06-05-2017, 10:38 AM   #1
Sprockett
New Member
11
Rep
14
Posts

Drives: Cayman S
Join Date: Jun 2017
Location: Calgary, AB

iTrader: (0)

DCT behavior at autocross

Does anyone here have first hand experience autocrossing with a DCT car? From what I can see, DCT gear ratios are extremely short which I imagine means using third with most courses (every course?). Are people shifting manually or does the car's auto mode downshift well enough to not think about it?
Appreciate 0
      06-06-2017, 12:35 AM   #2
MRufo
Private First Class
United_States
36
Rep
123
Posts

Drives: M2
Join Date: Oct 2016
Location: Gaia

iTrader: (0)

Sad as it is most of my best times have been using sport+ in auto mode. At the last event I tried many different combos and leaving it in 2nd using the torque was fastest.
I tried "all off" but that puts the car back in sport mode and I don't the response as well as sport plus.
Tires are 265 square star specs.
Appreciate 0
      06-06-2017, 12:37 AM   #3
MRufo
Private First Class
United_States
36
Rep
123
Posts

Drives: M2
Join Date: Oct 2016
Location: Gaia

iTrader: (0)

Sad as it is most of my best times have been using sport+ in auto mode. At the last event I tried many different combos and leaving it in 2nd using the torque was fastest.
I tried "all off" but that puts the car back in sport mode and I don't like the response as well as sport plus.
Tires are 265 square star specs.
Appreciate 0
      06-19-2017, 02:27 PM   #4
SkyShepherd
New Member
SkyShepherd's Avatar
2
Rep
7
Posts

Drives: BMW i3 Rex
Join Date: May 2016
Location: Langley, BC

iTrader: (0)

I've tried both, and I have found the manual mode to be fastest for me around a given course. I have been up into 3rd, but the courses I've run (only a few so far) have been mostly 2nd gear with a pop down into first for a slow tight 180. Left-foot braking in automatic mode seems to invoke additional intervention from the engine management that results in waiting for the car to relax control.
Appreciate 0
      06-19-2017, 02:51 PM   #5
MagnusT
Captain
MagnusT's Avatar
Sweden
538
Rep
624
Posts

Drives: BMW M2
Join Date: Jun 2016
Location: Stockholm

iTrader: (0)

I have been driving autox for 19 years (MT for 15 years). I have a friend who sometimes drives my M2 with me shotgun at autox events and track meets. He always drives in auto mode. And I'm impressed by the autosoftware. It is IMHO very good at being in the right gear at all times.

But I always always drive the DCT in manual mode (with DSC fully of or if in wet conditions sometimes in traction mode) Manual mode enables me to shift exactly where I want, even in the middle of a section. And sometimes choosing short shifting to limit the available power in low gear situations to limit risking loosing the rear. I LOVE the M2 DCT in manual mode :-)
Appreciate 1
Robin_NL8679.50
      06-22-2017, 05:14 AM   #6
tstafford
Private
tstafford's Avatar
30
Rep
66
Posts

Drives: 2017 M2
Join Date: Feb 2015
Location: Nashville

iTrader: (0)

Quote:
Originally Posted by MRufo View Post
Sad as it is most of my best times have been using sport+ in auto mode. At the last event I tried many different combos and leaving it in 2nd using the torque was fastest.
I tried "all off" but that puts the car back in sport mode and I don't the response as well as sport plus.
Tires are 265 square star specs.
Ok, I'll bite. Why is that sad?
Appreciate 0
      06-25-2017, 05:49 PM   #7
omasou
Colonel
omasou's Avatar
United_States
2080
Rep
2,999
Posts

Drives: BMWs
Join Date: Apr 2016
Location: US

iTrader: (4)

Garage List
2023 BMW S1000RR  [0.50]
2022 BMW F900XR  [3.00]
2022 BMW X6 40i  [0.50]
2020 BMW M2C  [9.50]
These are my results from today...

45.254 - MDM + Sequential 1 & 2
44.088 - MDM + Sequential 1 & 2
44.432 - DSC off + Sequential 1 & 2, I got too loose on a turn or 2
41.827 - Sport +
42.166 - Sport +
41.500 - Sport +

I was running stock in B Street on stock Contis (~5K of wear)...everyday air pressures...tires held up beautifully. Oh and this was my first ax in 15 years!!

For reference the B Street leader a 2016 Ford Focus RS running track tires, all wheel drive and competes nationally had a best time of 36.805.

Last edited by omasou; 06-25-2017 at 07:15 PM..
Appreciate 0
      06-25-2017, 10:57 PM   #8
MRufo
Private First Class
United_States
36
Rep
123
Posts

Drives: M2
Join Date: Oct 2016
Location: Gaia

iTrader: (0)

Quote:
Originally Posted by omasou View Post
These are my results from today...

45.254 - MDM + Sequential 1 & 2
44.088 - MDM + Sequential 1 & 2
44.432 - DSC off + Sequential 1 & 2, I got too loose on a turn or 2
41.827 - Sport +
42.166 - Sport +
41.500 - Sport +

I was running stock in B Street on stock Contis (~5K of wear)...everyday air pressures...tires held up beautifully. Oh and this was my first ax in 15 years!!

For reference the B Street leader a 2016 Ford Focus RS running track tires, all wheel drive and competes nationally had a best time of 36.805.

Yep. I get my fastest times in sport+ as well. It sounds like you're ready for some re71rs!
Appreciate 0
      06-26-2017, 07:25 AM   #9
omasou
Colonel
omasou's Avatar
United_States
2080
Rep
2,999
Posts

Drives: BMWs
Join Date: Apr 2016
Location: US

iTrader: (4)

Garage List
2023 BMW S1000RR  [0.50]
2022 BMW F900XR  [3.00]
2022 BMW X6 40i  [0.50]
2020 BMW M2C  [9.50]
Quote:
Originally Posted by MRufo View Post
Yep. I get my fastest times in sport+ as well. It sounds like you're ready for some re71rs!
I was going to ask that in a new thread but since you mentioned it.

The BS leader in his RS with track tires ran a 36.805. Another RS on his "stock" Michelin Pilot Sports ran a 37.634

So if we say this course was on average 38 seconds (looking at the results for all classes).

How many seconds could I reasonably expect to pickup without any other changes except tires?
Appreciate 0
      06-26-2017, 10:37 AM   #10
MagnusT
Captain
MagnusT's Avatar
Sweden
538
Rep
624
Posts

Drives: BMW M2
Join Date: Jun 2016
Location: Stockholm

iTrader: (0)

Quote:
Originally Posted by omasou View Post
I was going to ask that in a new thread but since you mentioned it.

The BS leader in his RS with track tires ran a 36.805. Another RS on his "stock" Michelin Pilot Sports ran a 37.634

So if we say this course was on average 38 seconds (looking at the results for all classes).

How many seconds could I reasonably expect to pickup without any other changes except tires?
1,5 - 2 seconds IMHO due to tires. Maybe more depending on how the course layout is.
Appreciate 1
omasou2079.50
      06-28-2017, 10:10 PM   #11
MRufo
Private First Class
United_States
36
Rep
123
Posts

Drives: M2
Join Date: Oct 2016
Location: Gaia

iTrader: (0)

Quote:
Originally Posted by MagnusT View Post
1,5 - 2 seconds IMHO due to tires. Maybe more depending on how the course layout is.
Yes
Appreciate 1
omasou2079.50
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 08:37 PM.




m2
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST