Tuning without IAT Data

[DrX]

It has been stated that IAT data on a Radix is bogus due to major heat soak. The sensor has been relocated to the cast intake. So much for accurate and consistent SD/AutoVE/Custom OS tuning with a Radix. :frown:

Any suggestions to get around the IAT issue?

[SSpdDmon]

**EDIT**Don't relocate the IAT to the filter area and plug the factory hole...

[Delco]

Relocate the IAT to the filter area and plug the factory hole.?.?.

AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH NOOOOOOOOOOOOOOOOOOOOOOO NEVER

never do that , what happens if the intercooler fails the engine has no way of knowing what is going on.

IAT in the manifold on a positive displacment combo is the best place for it , yes it will react a little slower due to the heat soak but it should still give the PCM the correct signals to correct for rising intake temps.

Usually I can see a 30 deg intake rise during the course of a dyno run when the aftercooler is not working efficnetly , you are looking for delta IAT to make correctiosn to keep the motor safe , under conditions of high airflow low boost the heatsoak is not a issue as the sensor is being cooled by the air rushing past it.

Make sure you are using a sensor that protrudes enough into the airstream and that will alleviate the heatsoak effect , remember also that at low airspeeds the air in the manifold is also being heated by this same heatsoak

[SSpdDmon]

My bad...I was thinking N/A...not boosted. Doh!

[Delco]

My bad...I was thinking N/A...not boosted. Doh!

Yes N/A you want it as close to actual outside temps as you can get :cheers:

[DrX]

Mag states that you risk engine damage if you rely on Radix IAT data due to the heat soak/slow response. So SD is not compatible with the Radix.

The slow IAT response could also expalin why AutoVE does not work well for me. Makes accurate SD idle tuning impossible as well. From my experience it would require a separate Idle IAT VE Multiplier table.

Does a more responsive IAT sensor exist?

[Delco]

Mag states that you risk engine damage if you rely on Radix IAT data due to the heat soak/slow response. So SD is not compatible with the Radix.

The slow IAT response could also expalin why AutoVE does not work well for me. Makes accurate SD idle tuning impossible as well. From my experience it would require a separate Idle IAT VE Multiplier table.

Does a more responsive IAT sensor exist?

Do you have a pic of the intake setup I assume you have a cooler inside the manifold to help control intake temps ?

Auto VE will be hard with a blown combo to do on the street as it is very hard to hold steady state for periods of time , auto ve doesnt really work if you cant hold each rpm /map point for at least 5-20 secs if you just drive through each point you will get transient data.

I do a lot of supercharged stuff with os3 and have done for nearly 4 years ( early development days of efilive before flashscan even existed ) IAT soak has never been a issue with careful tuning. You can weight how much the IAT affects timing through careful use of the rpm multiplier tables as well as the base IAt tables.
If the IAT rises above normal parameter then you start pulling timing pretty savagely to safeguard the engine , as well as adding more fuel.

The custom OS IAT compensation tables as well as the charge blending tables are your best friend here.



A good base tune doesnt take hours , it takes weeks/months to get a good baseline starting point before honing in on the power stuff

[DrX]

Here are a few pics. The IAT sensor is located under the snout. You can't see it in the first pic because of the hoses. You can see it internally in the third pic.

[Delco]

Here are a few pics. The IAT sensor is located under the snout. You can't see it in the first pic because of the hoses. You can see it internally in the third pic.

Looks a lot like the one I did on a hummer last week. Used a new custom OS for the 06 hummer ( a big thanks to Ross for doing it while still jetlagged from his trip to the states - what customer service :cheers: )

http://chipmaster.com.au/ftp/Hummer%20engine%20(Small).JPG


http://chipmaster.com.au/ftp/Hummerdyno%20(Small).JPG

The IAT in the manifold gave good consistant result .