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Moving IAT sensor

ls1camino

ls1camino

New member
So with my Twincharged setup, I am having trouble determining the IATs post blower, so my tuner recommended I move the IAT to the LIM. This will allow the PCM to read the exact IAT before the air goes into the heads. I've been reading up on it and a lot of Cobra guys have done this, so it's not super out-of-the-ordinary. Has anyone here done it? Where would be the best place to tap the LIM? Obviously someplace close to the TB side of the blower, so the harness doesn't have to be extended too far.
 


Won't matter in our platform.

The PCM doesn't use IAT to determine fueling, and the spark adder table is typically zero'd out, or close to it, by most tuners.
 
Chevy SS guys also do it. Thing is.. like Matt says. Does our setup use it for anything...

I personally have located it by the coil packs in the end of the LIM by #1. And in a GP harness since it comes from the center of the radiator in the wiring bundle...that should work out well.

I know 2003 SSEi posted a picture of how he did it..which is the same way I did it.
 
disconnect the IAT and connect a potentiometer in it's place and make up the tables so you can have a happy knob. best use of what's there.
 


Even though our PCMs don't use IATs, it should still be monitored by while tuning, so detonation can be predicted. I was seeing over 220* IATs pre-blower, which is not at all helpful to my tuner.
 
Its useful in diagnosing an undersized intercooling system.

However, I cannot see why it would help during tuning.

Our tables don't really go that high at all.
 
matt5112 said:
Its useful in diagnosing an undersized intercooling system.

However, I cannot see why it would help during tuning.

Our tables don't really go that high at all.
Click to expand...

High temps are never good and will result in knock, especially in the summer. Predictions have to be made for timing for when the temperature increases. Am I wrong in this assumption?

I was looking at the HP Tuners and it was reading in the high 220s during my dyno pulls. I am starting to doubt myself now, because the charge pipe from my turbo to my blower has never been super hot. Maybe we were getting false readings from the IAT...
 
Welcome to tuning a 3800.

Where nothing matters.

Just up the boost, and go about your business.

It takes time for the tubing to absorb that heat. If you only go wot for 4-5 seconds, it won't have time to heat up that much.
 
matt5112 said:
Welcome to tuning a 3800.

Where nothing matters.

Just up the boost, and go about your business.

It takes time for the tubing to absorb that heat. If you only go wot for 4-5 seconds, it won't have time to heat up that much.
Click to expand...

Interesting...how much boost can a 3.8 handle? I'm going with meth injection, so I'm confident I can up the boost while keeping the timing down.
 


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