The Top DSM Community on the Web

For 1990-1999 Mitsubishi Eclipse, Eagle Talon, Plymouth Laser, and Galant VR-4 Owners. Log in to remove most ads.

Please Support ExtremePSI
Please Support STM Tuned

ECMlink Maf + density comprehension.

This site may earn a commission from merchant
affiliate links, including eBay, Amazon, and others.

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

miliman13

10+ Year Contributor
1,957
276
Jan 1, 2011
tampa, Florida
I'm having a hard time understanding the instructions in the wiki:. http://www.ecmtuning.com/wiki/sdveadjsdratio

Help me out hear. Should the maf and the speed density sensors be all plugged in at the same time?

As in ait pressure and maf all wired in at same time? Since you have to cut the maf harness to even use the speed density sensors?

Sorry for the elementary question but a calculus book makes more sense to me then the wiki.
 
in my log, it "appears" the maf is dialed in nicely. thats from yrs of tuning only at idle with maf.

I was able to do so in 5 mns..... but i still dont know how to use that so stray to SD.

The wiki must be foolproof and i must be a special type of fool, because i dont get it.
 
I think the page you linked explains it pretty well. You essentially are taking the calibration your ecu uses for your existing MAF and then it "translates" that into useable data for your SD table. As long as you're following the instructions on that ecmlink page, you'll be fine.

And no, you are not using the gm iat sensor in conjunction with the MAF. Once you've run the SDratio tool, you disconnect the MAF and hook up the iat as described in the sd walk throughs.
 
Post log with your Speed Density setup. The one from the link is just MAF and cant adjust.
IN ECU Inputs set your Intake Temp Connector sensor - Probably GM IAT
SET MDP - whatever yours may be, mine is Omni 4 bar
then save pin assignments

Now add some captured values to your log too:
Baro, your IAT sensor, MDP sensor, SDRatio,Battery, LrndIdleAdj, ISCPosition, SDAirFlowPerRev,
also you are using an AEM wideband make sure it is accurate with what the gauge reads.

Here is a video:
You must be logged in to view this image or video.
 
I think the page you linked explains it pretty well. You essentially are taking the calibration your ecu uses for your existing MAF and then it "translates" that into useable data for your SD table. As long as you're following the instructions on that ecmlink page, you'll be fine.

And no, you are not using the gm iat sensor in conjunction with the MAF. Once you've run the SDratio tool, you disconnect the MAF and hook up the iat as described in the sd walk throughs.
this is were i get those eye rolls....:toobad:

But how do i translate it and use it as "data" into an SD table.
I keep reading the article but still have the same question.

Thanks by the way
 
You don't have to do anything with the data. Once you've got your MAF dialed in, you run the SDratio tool and it does it for you. Have you actually tried to follow the instructions in the page you linked? I'm not trying to be a jerk, but if you follow the instructions like they've listed, you'll be in good shape. Does that make sense?
 
{STEP 2: Data Capture
To use this tool, you need to capture some data from your ECU while you drive around on the mass airflow sensor, before switching the Base MAF setting to Speed Density.

NOTE: As normally installed, first generation (not Gen 2 or MAFT Pro) MAF translators get their ground from ECU sensor ground via the Mitsubishi MAF connector and draw a moderate amount of current, particularly when powering the GM MAF sensor at higher airflow, so the pressure and temperature readings seen by the ECU will change a little if you later unplug the GM MAF or MAF translator, upsetting the VE table calibration. Changing the translator's ground from ECU sensor ground to chassis ground instead will eliminate this effect. Cut the MAF translator's ground wire between the translator box and the Mitsubishi MAF connector and connect the end of this wire coming from the translator to chassis ground. Leave the wire end that remains on the translators Mitsubishi MAF connector isolated and insulated.

Add the following log items to your captured values (F10): SDRatio and MAP sensor. If SDRatio does not appear as an item available for capture, you first need to define the MAP sensor input on the Pin Assignments for Datalogging (PC-side) of the ECU Inputs tab.

SDRatio and engine displacement: It's very important to make sure SDRatio's engine displacement preference is set correctly to match your actual engine. Do this by double clicking on SDRatio in the graph legend.

You must be logged in to view this image or video.
The MAP sensor you want to log here is the one you have already configured in yourManifold pressure (MAP) field on the ECU Input tabs. An example of this is shown here. More details on configuring and installing this sensor can be found on theECMLink - Speed Density Setup page.

When attempting to initialize the SD VE Adjust (SDRatio) tool, the application will check your ECU Input tab to locate the MAP sensor. It will then attempt to find this sensor in your datalog. Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function.

While running off the mass airflow sensor, you basically just drive around logging the data above (SDRatio and MAP sensor) in your datalog. Try to drive under a variety of conditions (idle, cruise, wide open throttle). I like to locate a nice hilly area so I can vary throttle position, RPM and boost to generate the data I'm looking for. }

ok. this is the part i dont get : """ When attempting to initialize the SD VE Adjust (SDRatio) tool, the application will check your ECU Input tab to locate the MAP sensor. It will then attempt to find this sensor in your datalog. Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function.""""

If i took a log with the maft connected how do i log the GM sensor if i CANT because it would be connected to the MAF harness.
 
I never done it using a MAF. I just went straight to Speed Density. You can use SD VE Adjust CombinedFT.
But I would assume you have to:
Unhook your MAF setup your SPeed Density connection and log all the values so the ecu knows where they are at.
Then unhook your speed Density connection and plug back in your MAF. GO for a cruise and then plug your SPeed Density back in and use the Tool SD VE Adjust.
Seems like more work then its worth.

OR just unhook maf, install speed density, go for a cruise, use SD VE Adjust COmbinedFT a few times and have same results.
 
I never done it using a MAF. I just went straight to Speed Density. You can use SD VE Adjust CombinedFT.
But I would assume you have to:
Unhook your MAF setup your SPeed Density connection and log all the values so the ecu knows where they are at.
Then unhook your speed Density connection and plug back in your MAF. GO for a cruise and then plug your SPeed Density back in and use the Tool SD VE Adjust.
Seems like more work then its worth.

OR just unhook maf, install speed density, go for a cruise, use SD VE Adjust COmbinedFT a few times and have same results.
ill bring her off the stands tomorrow and see if i can just cut the crap out and switch it to sd and forget this dance.

thanks again . look forward to tomorrow.
 
{STEP 2: Data Capture
To use this tool, you need to capture some data from your ECU while you drive around on the mass airflow sensor, before switching the Base MAF setting to Speed Density.

NOTE: As normally installed, first generation (not Gen 2 or MAFT Pro) MAF translators get their ground from ECU sensor ground via the Mitsubishi MAF connector and draw a moderate amount of current, particularly when powering the GM MAF sensor at higher airflow, so the pressure and temperature readings seen by the ECU will change a little if you later unplug the GM MAF or MAF translator, upsetting the VE table calibration. Changing the translator's ground from ECU sensor ground to chassis ground instead will eliminate this effect. Cut the MAF translator's ground wire between the translator box and the Mitsubishi MAF connector and connect the end of this wire coming from the translator to chassis ground. Leave the wire end that remains on the translators Mitsubishi MAF connector isolated and insulated.

Add the following log items to your captured values (F10): SDRatio and MAP sensor. If SDRatio does not appear as an item available for capture, you first need to define the MAP sensor input on the Pin Assignments for Datalogging (PC-side) of the ECU Inputs tab.

SDRatio and engine displacement: It's very important to make sure SDRatio's engine displacement preference is set correctly to match your actual engine. Do this by double clicking on SDRatio in the graph legend.

You must be logged in to view this image or video.
The MAP sensor you want to log here is the one you have already configured in yourManifold pressure (MAP) field on the ECU Input tabs. An example of this is shown here. More details on configuring and installing this sensor can be found on theECMLink - Speed Density Setup page.

When attempting to initialize the SD VE Adjust (SDRatio) tool, the application will check your ECU Input tab to locate the MAP sensor. It will then attempt to find this sensor in your datalog. Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function.

While running off the mass airflow sensor, you basically just drive around logging the data above (SDRatio and MAP sensor) in your datalog. Try to drive under a variety of conditions (idle, cruise, wide open throttle). I like to locate a nice hilly area so I can vary throttle position, RPM and boost to generate the data I'm looking for. }

ok. this is the part i dont get : """ When attempting to initialize the SD VE Adjust (SDRatio) tool, the application will check your ECU Input tab to locate the MAP sensor. It will then attempt to find this sensor in your datalog. Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function.""""

If i took a log with the maft connected how do i log the GM sensor if i CANT because it would be connected to the MAF harness.

I understand where your confusion is now. To use the MAF to calibrate your SD table, you would need to have your MAP sensor connected to another ECU input.

For example, I have a plug and play MAP sensor in place of my MDP sensor on top of the intake manifold. This allows me to log the MAP sensor while running the MAF for calibration. For the record, they explained it at the very end of what you quoted.

"Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function"
 
I understand where your confusion is now. To use the MAF to calibrate your SD table, you would need to have your MAP sensor connected to another ECU input.

For example, I have a plug and play MAP sensor in place of my MDP sensor on top of the intake manifold. This allows me to log the MAP sensor while running the MAF for calibration. For the record, they explained it at the very end of what you quoted.

"Using the image above as an example, you would want to log the GM 3-bar sensor attached to the MDP input in order to use this function"
DING DING ***

i have an MDP connector not being used, so i can splice that up and connect my omni 4 bar to it and use the MAF at the same time ?>

any info on which wires connect to the 3
wires on my GM style pressure sensor.
{{ im asumming it will be the same as this from gofers article : http://www.dsmtuners.com/threads/wiring-logging-an-aem-3-5-bar-map-sensor.369338/ }}


log the GM 3-bar sensor attached to the MDP input
this did not make sence to me because i thought it ment input as in software and not connect it to the engine harness.
 
Last edited:
I understand where your confusion is now. To use the MAF to calibrate your SD table, you would need to have your MAP sensor connected to another ECU input.

For example, I have a plug and play MAP sensor in place of my MDP sensor on top of the intake manifold. This allows me to log the MAP sensor while running the MAF for calibration.


Kronus does that mean that if i remove my maf and run full time SD i can run my MAP in my MDP location and not have to wire it into the MAF harness.?
the only difference im seeing, is in the maf the BLUE (baro)connects to the orange . and at the MDP is connect to the green/black wire.

im assuming you can right? since people with the MAP mitsu style have no choice but im using the GM style and the wiki dictates i use the MAF harness and not the MDP.
 
Kronus does that mean that if i remove my maf and run full time SD i can run my MAP in my MDP location and not have to wire it into the MAF harness.?
the only difference im seeing, is in the maf the BLUE (baro)connects to the orange . and at the MDP is connect to the green/black wire.

im assuming you can right? since people with the MAP mitsu style have no choice but im using the GM style and the wiki dictates i use the MAF harness and not the MDP.
You can connect your MAP at your MDP and still run your MAF. Ecmlink allows you to designate your MDP input as various types of MAP sensors.

But, yes, connecting at the MDP location means you can leave your MAF connector alone, except you MUST connect your GMAIT through the correct wire in your MAF harness. There is no other input to the ECU that can interpret an IAT signal.

You could cut off the MDP connector and wire in the gm map connector there. The ECU will interpret the signal appropriately as you adjust your settings in the ecmlink software.

I strongly suggest your read back through the how tos carefully, because all of this and I mean all of it is explained clearly there.
 
as an update the GM style omni 4 bar connected the same way gopher connected his AEM in the linked article.

Using the above setting it to MDP it logged.
will have to exit stream to reflect once pinned.


Check out my log. tell me if you see anything.
So i can drive and just use the (SDRatio) and (SDCombinedFT) to "self tune" correct.?
 

Attachments

  • idle.sd.2.elg
    34.5 KB · Views: 73
Hi guys, I recently installed SD in my 1992 galant vr4, I am using MAF 609. When I set MAF Comp to SD, I get a rich idle. Attached is my idle logs with SD enabled/connected.

Do I need to cruise using SD as MAF Comp to use SDratio thing?

Thank you.
 

Attachments

  • log.2019.03.10-01-idle_sd_enabled.elg
    478.8 KB · Views: 55
Support Vendors who Support the DSM Community
Boosted Fabrication ECM Tuning ExtremePSI Fuel Injector Clinic Innovation Products Jacks Transmissions JNZ Tuning Kiggly Racing Morrison Fabrications MyMitsubishiStore.com RixRacing RockAuto RTM Racing STM Tuned

Latest posts

Build Thread Updates

Vendor Updates

Latest Classifieds

Back
Top