[tetsuo111]

rjhall hassmaschine Terraphantm justpete

Rjal frequently advocates Testo for data logging. JustPete uses a motorsports-caliber system. I'm aware of Dragy as well, and even Carly BMW includes a few primitive data logging features.

I tend to be a skeptic of Internet wisdom because there's so much "noise" relative to credible information. The value of monitoring data for improving performance is a given. Yet the number of people here in the E90 forum doing so seems limited to a handful of people. I think one of the reasons so few use data-logging is the specialized technical experience required to operate the hw and sw. More importantly is the experience needed to know which of the many parameters to monitor, identifying weak points before failure, and how to use the data logs to draw intelligent conclusions and implement changes.

I thought to start a discussion to establish best practices and share experiences on the topic. I'm just starting to use Carly's primitive data monitoring to monitor coolant temp, calculated air mass, IAT, TQ, and battery voltage. Carly only recently started working for data.

For the more experienced forum people, which parameters are you looking at and why? Are you willing to share your success stories and failures? I have no idea if the parameters I'm looking at are a good start point. I know that the answer must be it depends on what we're trying to accomplish, but for the purpose of our discussion, I'm mostly looking at general best practices and a starting point. I would like to gain a better understanding of the leverage points in the system and how to manipulate them for various goals, like targeting output at different motor speeds, thermodynamic optimization for different goals (power, reliability, efficiency), and having visibility on our normal operating conditions.

[rjahl]

Originally Posted by tetsuo111

rjhall hassmaschine Terraphantm justpete

Rjal frequently advocates Testo for data logging. JustPete uses a motorsports-caliber system. I'm aware of Dragy as well, and even Carly BMW includes a few primitive data logging features.

I tend to be a skeptic of Internet wisdom because there's so much "noise" relative to credible information. The value of monitoring data for improving performance is a given. Yet the number of people here in the E90 forum doing so seems limited to a handful of people. I think one of the reasons so few use data-logging is the specialized technical experience required to operate the hw and sw. More importantly is the experience needed to know which of the many parameters to monitor, identifying weak points before failure, and how to use the data logs to draw intelligent conclusions and implement changes.

I thought to start a discussion to establish best practices and share experiences on the topic. I'm just starting to use Carly's primitive data monitoring to monitor coolant temp, calculated air mass, IAT, TQ, and battery voltage. Carly only recently started working for data.

For the more experienced forum people, which parameters are you looking at and why? Are you willing to share your success stories and failures? I have no idea if the parameters I'm looking at are a good start point. I know that the answer must be it depends on what we're trying to accomplish, but for the purpose of our discussion, I'm mostly looking at general best practices and a starting point. I would like to gain a better understanding of the leverage points in the system and how to manipulate them for various goals, like targeting output at different motor speeds, thermodynamic optimization for different goals (power, reliability, efficiency), and having visibility on our normal operating conditions.

The reason why I am a strong proponent of Testo is its ability to maximize the BMW communication protocols above and beyond standard ODB logging tools.

The MSV70 and MSV80 do not give much processing priority to ODB commands. With these DMEs you should achieve one data command per 90 miliseconds. If you are trying to log 10 parameters using normal ODB PIDs your logging will slow down to about one cycle per second. Totally useless.

Using the BMW protocols. There are functions that allow the DME to report 30+ parameters per cycle. So that's 30 parameters every 100ms. Not great but good enough for our purposes.


What to log? Depends on your goals. Trouble shooting or performance monitoring. For trouble shooting you can look at target values vs. actual such as Vanos target vs. Actual. Actual will follow the target with some delay, milliseconds. If the solenoids are sticky, you will see it.

For performance, I knew the targets from my tune so I only looked at actual values. I like to watch the following:

Lamda Both wide band sensors
Ignition timing.
Exhaust Vanos
Intake Vanos
RPM
Vehicle speed
Reported calculated torque
Target torque
IAT
Coolant temp, sometimes
Eccentric cam position and target
Exhaust temp both sensors
Load
Knock sensor values both
MAP sensor value
MAS sensor value
Sometimes I would use the VE but the values were a little strange and its easy to calculate from the MAS and IAT

There might be other tools that capitalize on the BMW Ediabas protocols but I don't know of any. There are also a quark that slows down the data on the MSV70, I helped Pheno resolve that a few years ago.


I hope this information helps

Edit: add vehicle speed to logging parameter

[tetsuo111]

Originally Posted by rjahl

The reason why I am a strong proponent of Testo is its ability to maximize the BMW communication protocols above and beyond standard ODB logging tools.

The MSV70 and MSV80 do not give much processing priority to ODB commands. With these DMEs you should achieve one data command per 90 miliseconds. If you are trying to log 10 parameters using normal ODB PIDs your logging will slow down to about one cycle per second. Totally useless.

Using the BMW protocols. There are functions that allow the DME to report 30+ parameters per cycle. So that's 30 parameters every 100ms. Not great but good enough for our purposes.


What to log? Depends on your goals. Trouble shooting or performance monitoring. For trouble shooting you can look at target values vs. actual such as Vanos target vs. Actual. Actual will follow the target with some delay, milliseconds. If the solenoids are sticky, you will see it.

For performance, I knew the targets from my tune so I only looked at actual values. I like to watch the following:

Lamda Both wide band sensors
Ignition timing.
Exhaust Vanos
Intake Vanos
RPM
Vehicle speed
Reported calculated torque
Target torque
IAT
Coolant temp, sometimes
Eccentric cam position and target
Exhaust temp both sensors
Load
Knock sensor values both
MAP sensor value
MAS sensor value
Sometimes I would use the VE but the values were a little strange and its easy to calculate from the MAS and IAT

There might be other tools that capitalize on the BMW Ediabas protocols but I don't know of any. There are also a quark that slows down the data on the MSV70, I helped Pheno resolve that a few years ago.


I hope this information helps

Edit: add vehicle speed to logging parameter

Thanks, rjahl!

I wasn't aware of the bandwidth limitations of the DME suites. Good to know. I searched a couple of times for Testo, but only found monitoring hw/sw used for food service industry temperature applications. If you have a link or guidance on specific Testo apps for us, that would be great, thanks.

I'm of the opinion that learning to extract value from the data is the larger challenge, but I'm learning to crawl first, mostly by just monitoring parameters, to get a feel for operating ranges and how they respond under different conditions. One parameter of interest to me is coolant temp. Interestingly, on Carly the coolant sensor shows ~ 200 deg and higher. This doesn't pass the common sense test, does it? I'm also troubleshooting an emissions fault code. Thanks for the tip to monitor actual vs target. I'll do just that.

[rjahl]

Originally Posted by tetsuo111

Thanks, rjahl!

I wasn't aware of the bandwidth limitations of the DME suites. Good to know. I searched a couple of times for Testo, but only found monitoring hw/sw used for food service industry temperature applications. If you have a link or guidance on specific Testo apps for us, that would be great, thanks.

I'm of the opinion that learning to extract value from the data is the larger challenge, but I'm learning to crawl first, mostly by just monitoring parameters, to get a feel for operating ranges and how they respond under different conditions. One parameter of interest to me is coolant temp. Interestingly, on Carly the coolant sensor shows ~ 200 deg and higher. This doesn't pass the common sense test, does it? I'm also troubleshooting an emissions fault code. Thanks for the tip to monitor actual vs target. I'll do just that.

http://www.e90post.com/forums/showth...ighlight=testo

http://www.bimmerforums.com/forum/sh...ime-graph-view



Two links but there are many others. The stand alone version is the best.

Don't worry too much about coolant temp, It's pretty constant through a 7 second pull. Should run between 95C and 105C. The water pump and thermostat are controlled by the DME and there is a logic that defines the targets.

For starters I would watch the airflow / MAS, ignition advance Knock values and Lambda values. The rest should closely follow your tune. I think you will find that the load management and knock control will play havoc with your expected ignition advance.

If enough people would play, we could build a good database with the expected values. For obvious reasons, I've been spending more time with the N54 groups and the "MHD, take a look at my log" thread has a huge number of contributors. They have built public XDFs and public "how to tune files". All information made available by contributing members.

Funny, I have more information available to tune my N54 than I had with my N52 but less interest to actually do the work. Maybe I feel that it's no longer unexplored territory and it's not a challenge.

In my opinion the biggest issue with TestO is the need for a laptop running MS Windows. An Android version would be really great, Elm 327 compatibility would be icing on the cake