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




 

Post Reply
 
Thread Tools Search this Thread
      01-09-2012, 11:30 AM   #1
Mahlzeit
Lieutenant
United_States
37
Rep
582
Posts

Drives: 1M
Join Date: Jul 2007
Location: Location Location

iTrader: (0)

ECU Learning Octane

Question:

How long to wait and how to far to drive after fueling w/ high octane gasoline for the stock ECU to read and adjust and thus increase power? And, will the ECU eventually adjust back down to stock power levels once it figures out the octane is higher than 'normal'?

Why:

Looking for the optimal times to do a stock w/ Californian 91 vs high octane dyno runs. My butt dyno says ~4 miles after putting in a mixture of 100 octane and California's finest 91.
Appreciate 0
      01-09-2012, 12:18 PM   #2
Dackelone
European Editor
Dackelone's Avatar
Germany
10511
Rep
22,992
Posts

Drives: N54 e82
Join Date: Feb 2010
Location: Bayern, Germany

iTrader: (1)

I was told it takes sveral hundred kilometers (400+ kms) for the engine DME to fully adapt, say after the DME has been flashed/tuned. No idea how long it takes for the engine to adapt to higher octane fuel though. My guess is "some time/miles". It might just be that the engine has to go thru some cold start cycles, and cruising modes and WOT runs before it can take full advantage of the higher octane fuel.

I can tell you that normally I use SuperPlus (98 octane, which is close to 93/94 octane fuel in the states) fuel over here in Germany. When I go to Shell V-Power 100 or Aral Ultimate 102 octane - I notice the egine feels "different" right away. The engine revs smoother and its quieter - I think. It feels better too. Not sure IF thats all in my head or not.


Dack
Appreciate 0
      01-09-2012, 02:32 PM   #3
Franklin Joseph
Captain
57
Rep
820
Posts

Drives: BMW
Join Date: Aug 2007
Location: Texas

iTrader: (1)

i'm curious too...as i am planning to mix some VP MS109 race fuel when i hit the track.

Would clearing adaptation help?
Appreciate 0
      01-09-2012, 03:16 PM   #4
Mahlzeit
Lieutenant
United_States
37
Rep
582
Posts

Drives: 1M
Join Date: Jul 2007
Location: Location Location

iTrader: (0)

More butt dyno: 3rd gear defn pulls even harder than before, pretty damn addictive.

I suspect upping octane is a fun little mod-surrogate that could get you your mod fix while you scratch together money for permanent mods. Getting very curious about what sort of actual power increase you get w/ 100 octane.
Appreciate 0
      01-17-2012, 03:10 PM   #5
Franklin Joseph
Captain
57
Rep
820
Posts

Drives: BMW
Join Date: Aug 2007
Location: Texas

iTrader: (1)

anymore update on this? still feeling the power bump?
iirc, HPA dynoed their car with race fuel and made 20 rwhp and 10 rwtq.

i'm heading to the dyno this friday, and thinking of mixing some race fuel to see how it goes.

anyone try mixing with e85?
Appreciate 0
      01-17-2012, 03:47 PM   #6
Mahlzeit
Lieutenant
United_States
37
Rep
582
Posts

Drives: 1M
Join Date: Jul 2007
Location: Location Location

iTrader: (0)

Did a little octane cocktail again this past Monday (had it off). 5 gallons 100, 3 gallons 91. this time. And yep,... after few redline pulls, there is torque bump over CA 91 (don't forget my baseline is CA gas, not known for its performance characteristics TX premium gas might yield a higher baseline).

My local dyno shop didn't have dyno time available, so I went for an extended drive instead. Next time the kids, work and wife stars align - I plan to spend the cash on some before/after dynos.
Appreciate 0
      01-17-2012, 08:00 PM   #7
Mnime
First Lieutenant
24
Rep
391
Posts

Drives: 2015 Cayman GTS
Join Date: Jan 2011
Location: Dallas, TX USA

iTrader: (0)

i had the performance steering wheel put on my car a while back. The dealer had some fault code they couldnt clear and had to "re-install" all my cars electronics. It really sucked and I had really bad turbo lag for about a month (500 to 600 miles) and it just now seems like the car I had prior to the ECU software re-install. So I can back up Dackelone's comments of several hundred miles for the computer to "learn" how you drive.
Appreciate 0
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 04:40 AM.




1addicts
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