IAT (MAT) Sensor vs Timing Mystery Solved....
#1
Race Director
Thread Starter
IAT (MAT) Sensor vs Timing Mystery Solved....
I pulled up the stock IAT vs Temp map with LS1-Edit and here is what I found..
First of all a relocated IAT does NOT increase timing at all. It only keeps the PCM from retarding any.
Second, there is no timing pull until the temps hit 104 degrees! And even then it does not pull timing until the pedal is more than half way down.
Summary...
The 57 degree timing tricker is way overkill A resistor to keep it at 100 would do the same thing...
The Timing Tricker can not be learned out by the pcm as some others have speculated.
The IAT is ONLY used to retard timing in the event of very hot air entering the intake.
Look at the chart I copied. I only converted the temps from C to F
http://personal.atl.bellsouth.net/mi...0vs%20TEMP.xls
[Modified by chuckster, 10:33 PM 9/20/2002]
[Modified by chuckster, 10:37 PM 9/20/2002]
First of all a relocated IAT does NOT increase timing at all. It only keeps the PCM from retarding any.
Second, there is no timing pull until the temps hit 104 degrees! And even then it does not pull timing until the pedal is more than half way down.
Summary...
The 57 degree timing tricker is way overkill A resistor to keep it at 100 would do the same thing...
The Timing Tricker can not be learned out by the pcm as some others have speculated.
The IAT is ONLY used to retard timing in the event of very hot air entering the intake.
Look at the chart I copied. I only converted the temps from C to F
http://personal.atl.bellsouth.net/mi...0vs%20TEMP.xls
[Modified by chuckster, 10:33 PM 9/20/2002]
[Modified by chuckster, 10:37 PM 9/20/2002]
#2
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Re: IAT (MAT) Sensor vs Timing Mystery Solved.... (chuckster)
That is very good info to know. I only used the IAT resistor mod to retard timings for my nitrous setup. :cheers:
#3
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Re: IAT (MAT) Sensor vs Timing Mystery Solved.... (chuckster)
Chuckster, you´re right.
That´s why I fake the IAT sensor with a resistor to let it see hot temps and then to retard the timing on my NOS runs.
That´s how it works.
Michael
That´s why I fake the IAT sensor with a resistor to let it see hot temps and then to retard the timing on my NOS runs.
That´s how it works.
Michael
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Re: IAT (MAT) Sensor vs Timing Mystery Solved.... (chuckster)
What you do not know is that you see a low octane versus a high octane table in LS! Edit.
What can keep the timing in the high octane table is the computer comfortable with the air temp at 57 degrees. slow learning with your cup never full! There are many tables that have not been added to LS1 edit
Do not get me wrong it is a wonderful tool. From all of your post's that I
seen you are going to overload your mind, it may take a lifetime.I have 20 years of engine management experience i give you answers and you ask for different replys what do you want, I do not have all the answers. i tell doctors i won't work on their patients leave their corvette computer controls to me. You are looking for simple fixes in a complex system.
Get your a/f mixture at 12.8:1 to 13:1 and timing at 24 -28 Degrees with no KR and leave it alone or your going to break something vetetech
[Modified by vetetech, 6:10 AM 9/22/2002]
What can keep the timing in the high octane table is the computer comfortable with the air temp at 57 degrees. slow learning with your cup never full! There are many tables that have not been added to LS1 edit
Do not get me wrong it is a wonderful tool. From all of your post's that I
seen you are going to overload your mind, it may take a lifetime.I have 20 years of engine management experience i give you answers and you ask for different replys what do you want, I do not have all the answers. i tell doctors i won't work on their patients leave their corvette computer controls to me. You are looking for simple fixes in a complex system.
Get your a/f mixture at 12.8:1 to 13:1 and timing at 24 -28 Degrees with no KR and leave it alone or your going to break something vetetech
[Modified by vetetech, 6:10 AM 9/22/2002]
#5
Re: IAT (vetetech)
What you are saying is that the 57* IAT Tricker helps when you have some minor KR and would normally fall onto the Low-Octane timing table, but instead if you have the 57* Tricker it keeps you on the High-Octane table?
#7
Race Director
Thread Starter
Re: IAT (vetetech)
Sorry bro. I don't mean to insult you by asking others...It's like your Doctor analogy...I would never get an operation without a second opinion.... :D
Anyway I love information overload. I know I will make mistakes along the way but. I will get soooo much satisfaction learning this stuff for myself.. I know I will never be an expert but I think in the 1 week I have owned LS1-Edit I have learned more then most folks who have it a year...
Also..Please tell me more about what LS1-Edit does not do....This is important to me...If the PCM code is supposed to be secret and not public from GM then how do Steve Cole and Ed Wright program and what do they use...A Tech II.
Anyway I love information overload. I know I will make mistakes along the way but. I will get soooo much satisfaction learning this stuff for myself.. I know I will never be an expert but I think in the 1 week I have owned LS1-Edit I have learned more then most folks who have it a year...
Also..Please tell me more about what LS1-Edit does not do....This is important to me...If the PCM code is supposed to be secret and not public from GM then how do Steve Cole and Ed Wright program and what do they use...A Tech II.
#9
Race Director
Thread Starter
Re: IAT (scool93535)
So what value of resistance and wattage is needed to trick 57 degrees? :rolleyes:
I use one. :smash:
#11
Race Director
Thread Starter
Re: IAT (vetetech)
What you do not know is that you see a low octane versus a high octane table in LS! Edit.
What can keep the timing in the high octane table is the computer comfortable with the air temp at 57 degrees.
What can keep the timing in the high octane table is the computer comfortable with the air temp at 57 degrees.
But I am not sure what that has to do with the high and low octane tables...?
Are you inferring that the PCM will automatically switch to the Low Octane table if the IAT temps are too high?? Even if there is no K/R. If so then that has to be the one most important feature of the Timing tricker.. Unless of course you just use LS1-Edit and make both the high and low tables exactly the same.. :smash: :D
Yes I undertand the implications of doing this. However, if the K/R tables are left alone that will take care of it.