I'm starting this thread to try and compile as much detailed info about all of the different options for each way we can use IAT data with the speed density patches.

I would like to list the following for each:

-options available depending on ROM used

-which IAT option is used (0x0E or 0x03)

-Scaling changes (as well as ECUflash table scaling changes)

-location of scaling changes depending on which option you use

-where the sensor input is connected on the vehicle

-evoscan Request ID and formula for each option


So I know we have the option of using the fuel temp sensor, a GM IAT sensor connected to the fuel temp sensor input on the ECU, or a GM IAT sensor connected to the factory air temp sensor wires on the MAF plug.

If everyone can contribute any of the detailed info for each option so it's all in one place, I will update this first post as the info is compiled.

If there is already a single post with all of the DETAILED info on this, just send me a link and I will delete this thread. Thanks guys.

-Jamie

 

For a clean connection, I went with the Spoolin harness which connects from the IAT to the MAF connector with out having to use pins or splicing. Very resonable price concidering you get the harness and IAT Sensor in one package.

 

That's great but that's not useful unless you share the settings used in ECUFlash and Evoscan. That would be a good contribution to this thread if you wouldn't mind sharing.

-Jamie

 

https://www.evolutionm.net/forums/sh...hlight=log+iat

 

-where the sensor input is connected on the vehicle

Just answering one of the questions, didn't know you were looking for all or nothing.

 

No biggie. The locations are already known though, it's the other detailed info I was looming for

 

I posted a thread in which there is a rom uploaded with the original scaling from roadspike, and then there is an update scaling from donner. Also some logging information there.

 

I believe this is all the correct info for:

GM IAT sensor connected to MAF harness (temps are in Fahrenheit)
via Spoolinup SD IAT Plug n' Play Harness or hardwiring the sensor to the harness by connecting it to the RED/BLUE wire and the BLACK wire.

• SD IAT option set to 0x03
  
  
• SD MAT Scaling for IAT Scaling located in the Speed Density Programming section in ECUFlash needs to be sure the temp scaling for the table is set properly before editing any values. The correct scaling needs to be set to TempScale. The window bleow can be found by RIGHT-CLICKING the table and selecting "EDIT MAP...".
  
  
  
• Once the table scaling is confirmed to be set correctly, you need to confirm that the appropriate temperature scaling for the GM IAT in the right column of the table is set to the proper values. The correct values can be found HERE. If they don't already match the values currently in the table, copy and paste the values from the link provided.
  
  
• In evoscan, use MUT11 to log the actual air temp readings that will be used by the ECU in all of the maps when the car is running. MUT3A is the unscaled raw air temperature directly from the sensor itself. Here is the evoscan data if you do not have them already:

I want to make sure this is correct for everyone else before I finalize the info for this option.

 

Subscribed! Btw already got my car setup for the Spoolin up harness w/ gm iat on my car. how can i take a screen shot and ill post my tables up for everyone to see. Hope your doing good bro. and very informative thread. BTW does MUT 11 still work on the 3DSD roms or do they change from the 2d to 2d for logging.

 

I'm not actually sure if the formula for the MUT is the appropriate on to use since the "-40" is a Celsius conversion while "+32" is the Fahrenheit conversion. Someone will have to chime in and confirm that is the correct formula and RequestID to be using.

 

Yea ill see if i can get in touch with spoolin up. He helped me out before im sure he can answer the question if there needs to be a change to the MUT

 

where is the best place to weld iat sensors bung? Is that better place on uicp in the middle of TB and bov?

 

Generally very low on the UICP to keep it away from getting heat soaked from the engine bay radiant heat. This can cause warm-start issues at times.

-Jamie

 

thanks Jamie

 

Can't we leave the MAF plugged in and use the temp and baro off of that?. I'm sure it could be discreetly mounted out of the way.