E90Post
 


 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Powertrain and Drivetrain Discussions > N55 Turbo Engine Tuning and Exhaust Modifications - 335i Tuning > **infamous n55 torque dip**



Reply
 
Thread Tools Search this Thread
      01-30-2011, 12:50 PM   #23
black e
Lieutenant
black e's Avatar
34
Rep
522
Posts

Drives: DCT N55 135I
Join Date: May 2010
Location: Boca Raton

iTrader: (7)

Quote:
Originally Posted by shockin330i View Post
13.5psi map 1? If you can, can you send me your dyno files?


i don't have the files... i'm going back to the shop tomorrow to get them and to have them printed with STD correction so we can compare to everyone around here.

14~14.4 PSI peak falling to 11~10 PSI at 6300 RPM, again , more on this later
Appreciate 0
      01-30-2011, 01:27 PM   #24
jjurroz
Second Lieutenant
24
Rep
269
Posts

Drives: 2018 F80 M3 ZCP
Join Date: Sep 2010
Location: Ft. Lauderdale, FL

iTrader: (0)

Quote:
Originally Posted by shockin330i View Post
Notice black - e had the same dip.
Black e only had it (the dip) on map 0 (bypass mode) but not on map 1. On his dyno, with map 1, he has no dip where the stock one has a huge one.
Appreciate 0
      01-30-2011, 01:34 PM   #25
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by jjurroz View Post
Black e only had it (the dip) on map 0 (bypass mode) but not on map 1. On his dyno, with map 1, he has no dip where the stock one has a huge one.
Black e has a small dip but then corrects itself.
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      01-30-2011, 02:06 PM   #26
black e
Lieutenant
black e's Avatar
34
Rep
522
Posts

Drives: DCT N55 135I
Join Date: May 2010
Location: Boca Raton

iTrader: (7)

i'll tell you that the the dip IS created by the stock boost control, on the stock tune the car hits 10+ PSI (boost overshoot)then tries to correct it self over and over...more on this later (read tomorrow night)
Appreciate 0
      01-30-2011, 02:37 PM   #27
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by black e View Post
i'll tell you that the the dip IS created by the stock boost control, on the stock tune the car hits 10+ PSI (boost overshoot)then tries to correct it self over and over...more on this later (read tomorrow night)
That's too long
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      01-31-2011, 08:37 PM   #28
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Can I get some mother f'in torque on pump gas!!!!
procede new maps....
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      01-31-2011, 08:55 PM   #29
OpenFlash
United_States
1733
Rep
17,960
Posts

Drives: A Lot
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Garage List
What's funny is that i had to drop low end boost a bit because my 7DCT was slipping under 4000rpm. As it is now, the car only runs 10-13psi under 3500rpm. Valvtronic is great.
Appreciate 0
      01-31-2011, 09:05 PM   #30
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by shiv@vishnu View Post
What's funny is that i had to drop low end boost a bit because my 7DCT was slipping under 4000rpm. As it is now, the car only runs 10-13psi under 3500rpm. Valvtronic is great.
Would the 6AT need the same boost drop?
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      01-31-2011, 09:25 PM   #31
OpenFlash
United_States
1733
Rep
17,960
Posts

Drives: A Lot
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Garage List
Quote:
Originally Posted by shockin330i View Post
Would the 6AT need the same boost drop?
Nope... Neither will the 6MT. But how much torque could you possible want?
Appreciate 0
      01-31-2011, 09:45 PM   #32
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by shiv@vishnu View Post
Nope... Neither will the 6MT. But how much torque could you possible want?
I have a feeling we can hit 450tq with race and meth. I need to order a meth kit...
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      01-31-2011, 09:49 PM   #33
OpenFlash
United_States
1733
Rep
17,960
Posts

Drives: A Lot
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Garage List
Quote:
Originally Posted by shockin330i View Post
I have a feeling we can hit 450tq with race and meth. I need to order a meth kit...
450tq is perfectly do-able. Will probably take 16-17psi at 3000rpm. Along with race gas/meth of course.

Shiv
Appreciate 0
      01-31-2011, 10:02 PM   #34
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by shiv@vishnu View Post
450tq is perfectly do-able. Will probably take 16-17psi at 3000rpm. Along with race gas/meth of course.

Shiv
Let's do it! Lol
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      02-01-2011, 09:12 AM   #35
jjurroz
Second Lieutenant
24
Rep
269
Posts

Drives: 2018 F80 M3 ZCP
Join Date: Sep 2010
Location: Ft. Lauderdale, FL

iTrader: (0)

Quote:
Originally Posted by shiv@vishnu View Post
450tq is perfectly do-able. Will probably take 16-17psi at 3000rpm. Along with race gas/meth of course.

Shiv
sign me up!
Appreciate 0
      02-01-2011, 10:39 AM   #36
Sniz
Lieutenant General
Sniz's Avatar
648
Rep
10,587
Posts

Drives: e92 335 - gone // e36 M3 turbo
Join Date: Mar 2007
Location: Ellicott City, MD

iTrader: (1)

Quote:
Originally Posted by shockin330i View Post
Can I get some mother f'in torque on pump gas!!!!
procede new maps....
thats a nice looking dyno!
__________________
Appreciate 0
      02-01-2011, 11:20 AM   #37
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by BoostedE90 View Post
Got this run from this thread...
http://www.e90post.com/forums/showthread.php?t=481075

This curve doesn't appear to have a dip...
Graph is in the OP

And if you look at the stock torque it does have the same dip. The dip seems to have been corrected in the tuned graph.
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      02-01-2011, 11:23 AM   #38
OpenFlash
United_States
1733
Rep
17,960
Posts

Drives: A Lot
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Garage List
The dip is caused by boost control. It's an issue called "integral wind-up" that happens during a low rpm, high gear pull. During low engine speeds, the DME is unsuccessfully trying to reach the boost target. So the integral component of the pId system adds full positive correction. When boost target is finally achieved, the DME still has all this positive correction that it cant get rid of quickly enough. So boost overshoots for a moment. In the BMW, this causes a throttle closure and a big recovery dip. So nope, it has nothing to do with AFR, timing, etc,. Just boost control.

Shiv
Appreciate 0
      02-01-2011, 11:26 AM   #39
atlharry
Second Lieutenant
South Korea
2
Rep
251
Posts

Drives: 2011 335i Coupe
Join Date: Aug 2010
Location: somewhere in the US...

iTrader: (0)

Quote:
Originally Posted by shiv@vishnu View Post
The dip is caused by boost control. It's an issue called "integral wind-up" that happens during a low rpm, high gear pull. During low engine speeds, the DME is unsuccessfully trying to reach the boost target. So the integral component of the pId system adds full positive correction. When boost target is finally achieved, the DME still has all this positive correction that it cant get rid of quickly enough. So boost overshoots for a moment. In the BMW, this causes a throttle closure and a big recovery dip. So nope, it has nothing to do with AFR, timing, etc,. Just boost control.

Shiv
It takes 1200 RPM to correct a boost overshoot?!?! I find that hard to believe.

I'm not saying you're wrong... it's just hard to believe... Are there any datalogs to support that?

Edit: I'm sure you do. Can we see them?
Appreciate 0
      02-01-2011, 11:29 AM   #40
OpenFlash
United_States
1733
Rep
17,960
Posts

Drives: A Lot
Join Date: Sep 2006
Location: SF Bay, CA

iTrader: (0)

Garage List
Quote:
Originally Posted by atlharry View Post
It takes 1200 RPM to correct a boost overshoot?!?! I find that hard to believe.

I'm not saying you're wrong... it's just hard to believe... Are there any datalogs to support that?
Integral (the "I" in PID) is the slowest moving correction of the 3. It's meant to make long-term offsetting changes to compensate for changes in operating conditions/hardware/etc,. It's not intended to catch spikes. That's the "D" or derivative gain. And yes, plenty of datalogs to show this.
Appreciate 0
      02-01-2011, 11:46 AM   #41
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by shiv@vishnu View Post
The dip is caused by boost control. It's an issue called "integral wind-up" that happens during a low rpm, high gear pull. During low engine speeds, the DME is unsuccessfully trying to reach the boost target. So the integral component of the pId system adds full positive correction. When boost target is finally achieved, the DME still has all this positive correction that it cant get rid of quickly enough. So boost overshoots for a moment. In the BMW, this causes a throttle closure and a big recovery dip. So nope, it has nothing to do with AFR, timing, etc,. Just boost control.

Shiv
Quote:
Originally Posted by atlharry View Post
It takes 1200 RPM to correct a boost overshoot?!?! I find that hard to believe.

I'm not saying you're wrong... it's just hard to believe... Are there any datalogs to support that?

Edit: I'm sure you do. Can we see them?
This confirms that black e was right. Its a boost over shoot. He was/is suppose to have a full write up of his finding from his dyno results today.
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      02-01-2011, 11:52 AM   #42
black e
Lieutenant
black e's Avatar
34
Rep
522
Posts

Drives: DCT N55 135I
Join Date: May 2010
Location: Boca Raton

iTrader: (7)

Quote:
Originally Posted by atlharry View Post
It takes 1200 RPM to correct a boost overshoot?!?! I find that hard to believe.

I'm not saying you're wrong... it's just hard to believe... Are there any datalogs to support that?

Edit: I'm sure you do. Can we see them?



I'll show some logs of this later today...
Appreciate 0
      02-01-2011, 11:56 AM   #43
shockin330i
Brigadier General
shockin330i's Avatar
798
Rep
4,784
Posts

Drives: 2016 ZCP M3
Join Date: Jan 2007
Location: f y'all, I'm from Texas (RGV)

iTrader: (1)

Quote:
Originally Posted by black e View Post
I'll show some logs of this later today...
YOu said that sunday! lol
__________________
ERnie
2016 BSM/f80/ZCP
Appreciate 0
      02-01-2011, 01:28 PM   #44
dmboone25
Lieutenant General
dmboone25's Avatar
4971
Rep
10,200
Posts

Drives: 2024 Golf R / 2022 718 Spyder
Join Date: Sep 2006
Location: Dallas, TX

iTrader: (0)

Garage List
2007 E92 328i  [10.00]
2007 328i  [10.00]
Quote:
Originally Posted by shockin330i View Post
Would the 6AT need the same boost drop?
Quote:
Originally Posted by shiv@vishnu View Post
Nope... Neither will the 6MT. But how much torque could you possible want?
Shiv--why do you think this is for the DCT?

If that is an obvious question/answer I apologize.

Coming from my 2008 N54/MT 135 to the 2011 N55/DCT 135, I swear the new one feels faster stock...I think it may just be the way that the transmission shifts...
__________________
Past rides: 2016 981 BGTS, 2020 MINI JCW, 2017 F80, 2015 981 CS, 2014 F22 235, 2011 E82 135, 2008 E82 135, 2007 E92 328, 2007 E92 328 (My lady drives an OG M2. So does my dad)
Appreciate 0
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 09:34 AM.




e90post
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