The IAT plugs into the intake elbow and tells the PCM the Internal Air Temp correct? What exactly does the PCM do with the IAT parameters? We figured out today that my buddy didn't have his plugged into his elbow on his 383, in fact the wires were cut (it was removed from previous owners wiring harness for whatever reason). We spliced a spare plug in from an old harness and just curious what it does technically for the PCM and how the car will run.

 

Actually the IAT sensor sends a voltage reading to the PCM. The heat passing by it creates resistance which sends a lower voltage to the PCM. Higher temp= more resistance, Lower temp= less resistance. The PCM uses this input as well as MAF, MAP and O2 to calculate the A/F ratio. That's why they sell a IAT relocation kit that moves the sensor further away from the throttle body to create a richer condition, if the wires are cut it will create a leaner condition because an open connection is infinite resistance thus sending a higher input voltage to the PCM. Hope this helps.

 

Very good input, thank you sir. He's running rich and we've pulled out fuel throughout the rpm ranges and still burns your eyes and blows a little black on high revs. Hopefully this will help his tuning along with more tweaking. He's using LT1 Edit but honestly most of it is over both our heads. I'd love to find a site that explained how it all different parameters work, what they do, how you should tune them. Even with my other buddys FAST system it was a major pain just to find any documentation on "how to tune 101".

Wonder if BigStuff includes some "how-to" info with their setup.

 

Ive been told the iat doesnt play that big a role in our cars.

 

Well if You are that into tuning maybe You or one of Your buddies should look into efi university they are in So. Cal. there is a website that will give You all kinds of info. I think there is a two day course and I think it costs about $1500. Just something to think about.