BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Engine, Transmission, Exhaust, Drivetrain, ECU Software Modifications
 
Steve Thomas BMW
Post Reply
 
Thread Tools Search this Thread
      07-03-2009, 08:43 AM   #1
jml
Captain
 
jml's Avatar
 
Drives: E90M3
Join Date: Dec 2008
Location: Austin, TX

Posts: 984
iTrader: (2)

Dyno of difference between strong/weak adaptation?

Just curious to see if anyone has been able to document a power improvement/loss due to different ECU adaptations. My E46 (and now the E90), after a track weekend, feels much stronger around town, even in the 100 degree heat. The magnitude is a lot like the difference between the summer and winter temps - pretty dramatic. I've used the dynolicious iphone app on the E90, which with questionable accuracy, shows a 20Hp improvement in the mid range, and 10HP at the top end.

With that difference, I question the improvements tuners claim with various go-fast parts (especially on the E90 where people are peeing all over themselves over 10HP).
jml is offline  
0
Reply With Quote
      07-03-2009, 08:59 AM   #2
lucid
Major General
 
lucid's Avatar
 
Drives: E30 M3; Expedition
Join Date: Apr 2007
Location: USA

Posts: 8,034
iTrader: (0)

Interesting question. I was thinking about the exact same thing. I just am not sure if it is my perception though. I've been thinking that getting a rush on the track, and driving at WOT and close to redline for a long time might alter my perception of the car afterwards. Regardless, the car indeed "seems" to respond differently after a track weekend. It would be interesting to test this somehow.
__________________
lucid is offline   United_States
0
Reply With Quote
      07-03-2009, 01:33 PM   #3
dcstep
Brigadier General
 
Drives: '09 Cpe Silverstone FR 6MT
Join Date: Nov 2008
Location: Colorado

Posts: 4,927
iTrader: (0)

Garage List
2009 M3  [4.00]
I know that it cost money, but not a ton, so maybe someone should do a before and after dyno run on a really dynamometer. 20 hp is HUGE and would only trust it on a "real" dyno.

I don't think there's anything there. I did a dyno run with a 70/30 mix of 91/100-octane. I then put in a 50/50 blend, ran an autocross (which is only a few minutes at full throttle), but the car did indeed "feel stronger" the next day. The very next day I went to the dyno and I'd lost 1 or 2-hp as compared to the 70/30 mix. I don't know what it is, but I think that the feeling of added power is psychological.

Dave
__________________
dcstep is offline   United_States
0
Reply With Quote
      07-03-2009, 01:41 PM   #4
jml
Captain
 
jml's Avatar
 
Drives: E90M3
Join Date: Dec 2008
Location: Austin, TX

Posts: 984
iTrader: (2)

Quote:
Originally Posted by dcstep View Post
I know that it cost money, but not a ton, so maybe someone should do a before and after dyno run on a really dynamometer. 20 hp is HUGE and would only trust it on a "real" dyno.

I don't think there's anything there. I did a dyno run with a 70/30 mix of 91/100-octane. I then put in a 50/50 blend, ran an autocross (which is only a few minutes at full throttle), but the car did indeed "feel stronger" the next day. The very next day I went to the dyno and I'd lost 1 or 2-hp as compared to the 70/30 mix. I don't know what it is, but I think that the feeling of added power is psychological.

Dave
How many miles at the autocross at full throttle do you think? I've heard it takes 50-100 miles for the engine to shift adaptation. At the track I go to the car spends probably 300 miles at WOT at speeds between 80 and 140 80% of the time over two days.

Sean from Discovery Automotive told me to reset adaptation on the race tune for my E46 at the track to get the most power out of it. I wish I knew more about how the ECU adaptation worked to understand what is really going on.
jml is offline  
0
Reply With Quote
      07-03-2009, 04:18 PM   #5
dcstep
Brigadier General
 
Drives: '09 Cpe Silverstone FR 6MT
Join Date: Nov 2008
Location: Colorado

Posts: 4,927
iTrader: (0)

Garage List
2009 M3  [4.00]
Quote:
Originally Posted by jml View Post
How many miles at the autocross at full throttle do you think? I've heard it takes 50-100 miles for the engine to shift adaptation. At the track I go to the car spends probably 300 miles at WOT at speeds between 80 and 140 80% of the time over two days.

Sean from Discovery Automotive told me to reset adaptation on the race tune for my E46 at the track to get the most power out of it. I wish I knew more about how the ECU adaptation worked to understand what is really going on.
I'm just telling you that my car "felt" stronger after only about 8-minutes at mostly full throttle. It actually measured weaker by a couple of hp.

Go ahead, put your car on a real dyno and post the runs for us to see. It'd be interesting to compare it to your iPhone read outs to validate that gizmo.

Dave
__________________
dcstep is offline   United_States
0
Reply With Quote
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
Forum Jump


All times are GMT -5. The time now is 08:04 AM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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