E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > Tuning & Tech > Forced Induction Forum Sponsored by Active Autowerke

Forced Induction Forum Sponsored by Active Autowerke
Discuss supercharging, turbocharging and even nitrous and water injection here.
Sponsored by Active Autowerke

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 01-22-2013, 02:14 PM   #1
luke@maximumpsi
Sponsor
 
Join Date: Nov 2012
Location: Linden NJ
Posts: 137
My Ride: 750hp E36 NickG Tune
Maximum PSI/Technique Tuning Stock DME Tuning Solutions - Single Bank Conversion

Hey guys,

As more stock DME tuning solutions become available for the turbo E46 M3 world, a few questions have been asked regarding the way we choose to tune the MSS54 ECU compared to others.

I wanted to start a thread outlining one of the major tuning hurtles faced by our team, more specifically Nick G, and how we choose to find a solution to the problem rather than try and work around it.

From the factory, the MSS54 ECU controls the engine's fueling as if it was actually 2 separate 3-cylinder engines (bank1 and bank2). This was possible because cylinders 1-3 had their own dedicated oxygen sensor, and cylinder 4-6 had another sensor. When installing a single turbocharger, the exhaust gasses from all 6 cylinders get combined together. Merely installing both pre-cat sensors into the downpipe will not work. The reason is because the ECU 'samples' the oxygen sensor signal at finite points in time; it first measures the bank 1 sensor, then 10 milliseconds later, it measures the bank 2 sensor. In those 10ms, the output of sensor 2 will vary SLIGHTLY from that of sensor 1. The ECU will interpret that slightly different reading from sensor 2 and calculate a different fuel modifier (aka, integrator) than bank 1. The result will be a different mixture in bank 1 than in bank 2. Over time, the two banks will become out of sync. One bank will end up being 25% rich, and the other 25% lean. The AVERAGE will be 0% from stoich, so the ECU thinks everything is fine, but clearly it is not, and the engine will run poorly.

There are a few ways to try and manage this exhaust gas integration:

1) Tie both bank 1 and bank 2 oxygen sensor wires together.

This won't work as the original problem still exists; the sampling of the bank2 line is still later than the bank1 line. This ends up causing the same problem as described above.

2) Disable lambda control in the ECU

While this method will make the ECU happy, it is clearly not the 'right' solution. Disabling the lambda control has many more CONS than PROS. The cons are increased fuel consumption, increased emissions, inability of the ECU to detect and compensate for engine and sensor wear, automatic failure of emissions testing, and on and on. Frankly, there really aren't any pros.

3) Rewrite the ECU's control code to work with 1 bank

This is the solution Technique Tuning implemented. The software was rewritten to work with only 1 pre-cat oxygen sensor, and 1 post-cat oxygen sensor. The original bank 2 sensors can be completely unplugged and eliminated from the vehicle. No simulators or resistors need to be installed due to their absence. No fault codes will be set or stored due to the missing oxygen sensors. The ECU will base fueling for all of the cylinders on the single oxygen sensor installed. There is no chance of any contention between bank1 and bank2 since the ECU now sees the engine as one single bank.

You will notice that the exhaust that comes with our kit will only have with 2 ports for the factory O2 sensors (3 if the customer needs an aftermarket O2 sensor). In our installation instruction you will aslo find that you unplug and remove both bank 2 O2 sensors.

Here are some pics to give you an idea of what I am talking about. Feel free to ask any questions you have!









-Luke
__________________

Luke King - Sales@maximumpsi.com
908-290-3571
luke@maximumpsi is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 01-22-2013, 02:50 PM   #2
TrippinBimmer
Registered User
 
Join Date: Jan 2008
Location: Ridgeland, MS
Posts: 5,384
My Ride: ZHP Custom Stage 3.5
Send a message via AIM to TrippinBimmer Send a message via Yahoo to TrippinBimmer
Nice! I can't wait to get my kit...
TrippinBimmer is offline   Reply With Quote
Old 01-22-2013, 03:10 PM   #3
02black330ci
Registered User
 
Join Date: Mar 2005
Location: ^^ E46FANATICS ^^
Posts: 1,814
My Ride: spaceship
Again, that is some SOLID dev work from Nick G!! Few questions.... What happens to the EGT sensor from Bank 2? Are you guys planning on eventually providing higher horsepower stages with the DME tune, ie 650 whp, 750 whp, etc? Any way to adapt (or future plans) E85 to the factory DME tune with an addition of an ethanol content sensor as real time % feedback?

Again, keep up the great work!!!
__________________






02black330ci is offline   Reply With Quote
Old 01-22-2013, 03:33 PM   #4
MachRc
E46Fanatic
 
MachRc's Avatar
 
Join Date: Sep 2002
Location: City of Angels
Posts: 6,481
My Ride: 2003 Technik S1 M3
thanks for the indepth explanation!
__________________

"We've come a long long way together. Through the hard times and the good.
I have to celebrate you baby,.. I have to praise you like I should.."
MachRc is online now   Reply With Quote
Old 01-22-2013, 03:48 PM   #5
Think0rz
Registered User
 
Join Date: Apr 2011
Location: Yonkers, NY
Posts: 235
My Ride: 05 AW M3
Quote:
Originally Posted by 02black330ci View Post
Again, that is some SOLID dev work from Nick G!! Few questions.... What happens to the EGT sensor from Bank 2? Are you guys planning on eventually providing higher horsepower stages with the DME tune, ie 650 whp, 750 whp, etc? Any way to adapt (or future plans) E85 to the factory DME tune with an addition of an ethanol content sensor as real time % feedback?

Again, keep up the great work!!!
While I cant comment you are definitely in sync with the guys at the shop. E85
__________________
Think0rz is online now   Reply With Quote
Old 01-22-2013, 04:00 PM   #6
02black330ci
Registered User
 
Join Date: Mar 2005
Location: ^^ E46FANATICS ^^
Posts: 1,814
My Ride: spaceship
Quote:
Originally Posted by Think0rz View Post
While I cant comment you are definitely in sync with the guys at the shop. E85
__________________






02black330ci is offline   Reply With Quote
Old 01-22-2013, 04:20 PM   #7
E85head
Registered User
 
Join Date: Jun 2012
Location: Car
Posts: 178
My Ride: E46 M3
Quote:
Originally Posted by Think0rz View Post
While I cant comment you are definitely in sync with the guys at the shop. E85
This!
E85head is offline   Reply With Quote
Old 01-22-2013, 05:43 PM   #8
PEI330Ci
58mm of Bliss
 
PEI330Ci's Avatar
 
Join Date: Jul 2003
Location: PEI,Canada
Posts: 3,993
My Ride: 330i, 330Ci
Quote:
Originally Posted by TrippinBimmer View Post
Nice! I can't wait to get my kit...
Did you win the lotto or something?

PEI330Ci is offline   Reply With Quote
Old 01-23-2013, 10:33 AM   #9
luke@maximumpsi
Sponsor
 
Join Date: Nov 2012
Location: Linden NJ
Posts: 137
My Ride: 750hp E36 NickG Tune
Guys,

As Dexter has precluded to, we are currently working on several higher octane fueling options with the shop turbo M3. One of which is e85. There is a lot of risk invoved with offering a solution to pump "e85" to the masses as the ethonal content can vary significantly from day to day and pump to pump. Once we feel confident with the results with the shop car, we might offer them as an upgrade path to the current offering.
__________________

Luke King - Sales@maximumpsi.com
908-290-3571

Last edited by luke@maximumpsi; 01-23-2013 at 10:35 AM.
luke@maximumpsi is offline   Reply With Quote
Old 01-23-2013, 01:04 PM   #10
FragNasty
Registered User
 
Join Date: Feb 2010
Location: NC
Posts: 171
My Ride: Car
This is probably a newby type question to you guys but...

Why not install the pre-cat O2 sensors pre-turbo and go with a twin-scroll setup where each bank takes measurements from a scroll fed by 3 cylinders? Mike mentioned that it was not possible for some reason but never explained why.

Obviously the pos-cat O2 sensors are going to take measurements from exhaust that is a mix of the two pre-cat scrolls. But if the DME relies on pre-cat sensors for its AF calculations then that shouldn't be a problem.

If memory serves, the N54 (the first generation twin-turbo E9x 335i engine) is a twin turbo that managed to keep the two banks separate all the way through the cat.

The N55 (the second gen twin-scroll 335i engine) has a twin scroll turbo. It appears to have only a pair os sensors, one pre-cat and one pos-cat so BMW went the route that Nick choose for this kit it seems. Is that right?

Thanks in advance.

Quote:
Originally Posted by luke@maximumpsi View Post
Hey guys,

As more stock DME tuning solutions become available for the turbo E46 M3 world, a few questions have been asked regarding the way we choose to tune the MSS54 ECU compared to others.

I wanted to start a thread outlining one of the major tuning hurtles faced by our team, more specifically Nick G, and how we choose to find a solution to the problem rather than try and work around it.

From the factory, the MSS54 ECU controls the engine's fueling as if it was actually 2 separate 3-cylinder engines (bank1 and bank2). This was possible because cylinders 1-3 had their own dedicated oxygen sensor, and cylinder 4-6 had another sensor. When installing a single turbocharger, the exhaust gasses from all 6 cylinders get combined together. Merely installing both pre-cat sensors into the downpipe will not work. The reason is because the ECU 'samples' the oxygen sensor signal at finite points in time; it first measures the bank 1 sensor, then 10 milliseconds later, it measures the bank 2 sensor. In those 10ms, the output of sensor 2 will vary SLIGHTLY from that of sensor 1. The ECU will interpret that slightly different reading from sensor 2 and calculate a different fuel modifier (aka, integrator) than bank 1. The result will be a different mixture in bank 1 than in bank 2. Over time, the two banks will become out of sync. One bank will end up being 25% rich, and the other 25% lean. The AVERAGE will be 0% from stoich, so the ECU thinks everything is fine, but clearly it is not, and the engine will run poorly.

-Luke

Last edited by FragNasty; 01-23-2013 at 01:07 PM.
FragNasty is offline   Reply With Quote
Old 01-23-2013, 06:04 PM   #11
PEI330Ci
58mm of Bliss
 
PEI330Ci's Avatar
 
Join Date: Jul 2003
Location: PEI,Canada
Posts: 3,993
My Ride: 330i, 330Ci
Quote:
Originally Posted by FragNasty View Post
This is probably a newby type question to you guys but...

Why not install the pre-cat O2 sensors pre-turbo and go with a twin-scroll setup where each bank takes measurements from a scroll fed by 3 cylinders? Mike mentioned that it was not possible for some reason but never explained why.
Pressure affects O2 sensors...or more specifically the readings. Sticking them pre-turbo would skew the response.

If you look at the newly introduced McLaren ECU used by Nascar, they have an external 4 channel Lambda controller used for each cylinder bank with a pressure sensor integrated. Being that the Nascar engines have a fairly free-flowing exhaust....and they have chose to go this route...kind of highlights the effect. If I was to try and run the setup as you've suggested, I would use the AEM/Nascar box as described above.
PEI330Ci is offline   Reply With Quote
Old 01-23-2013, 07:59 PM   #12
FragNasty
Registered User
 
Join Date: Feb 2010
Location: NC
Posts: 171
My Ride: Car
Quote:
Originally Posted by PEI330Ci View Post
Pressure affects O2 sensors...or more specifically the readings. Sticking them pre-turbo would skew the response.

If you look at the newly introduced McLaren ECU used by Nascar, they have an external 4 channel Lambda controller used for each cylinder bank with a pressure sensor integrated. Being that the Nascar engines have a fairly free-flowing exhaust....and they have chose to go this route...kind of highlights the effect. If I was to try and run the setup as you've suggested, I would use the AEM/Nascar box as described above.
Thanks.

It makes perfect sense now. In a previous thread you touched on something along these lines as I recall now.
FragNasty is offline   Reply With Quote
Old 01-23-2013, 08:09 PM   #13
mike@maximumpsi
boost junky
 
mike@maximumpsi's Avatar
 
Join Date: Dec 2010
Location: Linden, NJ
Posts: 547
My Ride: 02M3T, 97M3T
Quote:
Originally Posted by PEI330Ci View Post
Pressure affects O2 sensors...or more specifically the readings. Sticking them pre-turbo would skew the response.

If you look at the newly introduced McLaren ECU used by Nascar, they have an external 4 channel Lambda controller used for each cylinder bank with a pressure sensor integrated. Being that the Nascar engines have a fairly free-flowing exhaust....and they have chose to go this route...kind of highlights the effect. If I was to try and run the setup as you've suggested, I would use the AEM/Nascar box as described above.
Beat me to it. The N54 has two completely separate banks, and even still, the sensors are all downstream of the turbos. I have not looked at the N55 layout but I assume it has a single pre and post cat O2 sensor, and both are after the turbo.
__________________
02 M3 - Maximum PSI S2 turbo kit - 10.43@135.81, stock motor, stock ecu
97 M3 - Maximum PSI turbocharged - 9.16@163.37, first in the 9's
Maximum PSI - Home of the quickest BMW's in the US
Click here for E46Fanatics 1/4 mile standings
Email us at sales@maximumpsi.com!
Like us on facebook to follow our latest builds and upcoming events! - facebook.com/maximumpsi
mike@maximumpsi is offline   Reply With Quote
Old 01-24-2013, 01:41 PM   #14
02black330ci
Registered User
 
Join Date: Mar 2005
Location: ^^ E46FANATICS ^^
Posts: 1,814
My Ride: spaceship
Quote:
Originally Posted by luke@maximumpsi View Post
Guys,

As Dexter has precluded to, we are currently working on several higher octane fueling options with the shop turbo M3. One of which is e85. There is a lot of risk invoved with offering a solution to pump "e85" to the masses as the ethonal content can vary significantly from day to day and pump to pump. Once we feel confident with the results with the shop car, we might offer them as an upgrade path to the current offering.
Luke thanks for the response!! Keep the info coming and keep up the good work guys.
__________________






02black330ci is offline   Reply With Quote
Old 02-19-2013, 12:12 AM   #15
BrianSpilner
Registered User
 
Join Date: Feb 2006
Location: Chicago - Greece
Posts: 463
My Ride: Max PSI Stage 2
How is it possible to tune the OEM DME for E85 when the percentages of Ethanol at each pump is different? I am assuming that a flex fuel sensor needs to be integrated somehow into the DME?
__________________
Follow Me: Facebook | Youtube | Zima Motorsports
Follow My Builds: Max PSI Stage 2 E46 M3 Turbo Build | 1972 2002 Restomod Build
2004 BMW E46 ///M3 | Maximum PSI Stage 2 Turbo | SMGII | Non-Catted | Epic Motorsports Rod Bearing Kit | ARP Head Studs | Bimmerworld 3.5" Non-Resonated Single Race Exhaust

Last edited by BrianSpilner; 02-19-2013 at 12:12 AM.
BrianSpilner is offline   Reply With Quote
Old 02-19-2013, 06:14 AM   #16
mike@maximumpsi
boost junky
 
mike@maximumpsi's Avatar
 
Join Date: Dec 2010
Location: Linden, NJ
Posts: 547
My Ride: 02M3T, 97M3T
Correct
__________________
02 M3 - Maximum PSI S2 turbo kit - 10.43@135.81, stock motor, stock ecu
97 M3 - Maximum PSI turbocharged - 9.16@163.37, first in the 9's
Maximum PSI - Home of the quickest BMW's in the US
Click here for E46Fanatics 1/4 mile standings
Email us at sales@maximumpsi.com!
Like us on facebook to follow our latest builds and upcoming events! - facebook.com/maximumpsi
mike@maximumpsi is offline   Reply With Quote
Old 02-19-2013, 06:39 AM   #17
E85head
Registered User
 
Join Date: Jun 2012
Location: Car
Posts: 178
My Ride: E46 M3
Eta? ^
E85head is offline   Reply With Quote
Old 02-19-2013, 03:31 PM   #18
luke@maximumpsi
Sponsor
 
Join Date: Nov 2012
Location: Linden NJ
Posts: 137
My Ride: 750hp E36 NickG Tune
We are currently working on the calibration with an upgraded fuel system as we speak! There is a good deal of R&D that is going to be required to make the E85 option commercially available. I would assume the 109 calibration with switchable maps will be available prior.
__________________

Luke King - Sales@maximumpsi.com
908-290-3571

Last edited by luke@maximumpsi; 02-19-2013 at 03:32 PM. Reason: Auto-save 1361309520
luke@maximumpsi is offline   Reply With Quote
Old 02-19-2013, 03:37 PM   #19
E85head
Registered User
 
Join Date: Jun 2012
Location: Car
Posts: 178
My Ride: E46 M3
Are you certain that the stock DME is capable of supporting a flexfuel sensor? Or are you looking at other options?
E85head is offline   Reply With Quote
Old 02-19-2013, 04:01 PM   #20
luke@maximumpsi
Sponsor
 
Join Date: Nov 2012
Location: Linden NJ
Posts: 137
My Ride: 750hp E36 NickG Tune
We are confident! Only the stock DME will be used!
__________________

Luke King - Sales@maximumpsi.com
908-290-3571
luke@maximumpsi is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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 On
Censor is ON





All times are GMT -5. The time now is 10:20 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use