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Consistencey through resister.

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Old 07-30-2013, 08:25 AM
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Default Consistencey through resister.

I have a 00 WS6 and I am looking to put a resister in the air temp box to keep the car consistent. Wondering the best way to build one. I need a plug w/ the male end on it (wires coming off the back to wire the resister ) What is a good plug to use and am I doing this right?
Old 07-30-2013, 09:11 AM
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I want to bypass the Intake Air Temp Sensor.
Old 07-30-2013, 10:26 AM
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Originally Posted by Tire Fryer
I want to bypass the Intake Air Temp Sensor.
Tuned correctly, there is no need.
Old 07-30-2013, 08:41 PM
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Originally Posted by Ed Wright
Tuned correctly, there is no need.
This...there's no one trick to making a car run consistent. If your tune is right, the suspension is dialed in correctly and you do the same thing every time, the car will be consistent.
Old 07-30-2013, 09:57 PM
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I would not do it that way. I have tried it myself a long time ago and it didn't work. You need to eliminate any variables and there are a lot of them. Try to run the same coolant temp on every pass. EWP will help. Get rid of all the accessories on the engine. As they heat up or cool off resistance changes. Anything you can think of that is a variable, get rid of it if possible. The only thing you can't change is weather and track condition. Set your car up to hook well. Get your burnout the same every time. stage the same each run.
Old 07-30-2013, 11:39 PM
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The purpose of the IAT sensor is to allow the PCM to compensate for air-temperature changes and thereby maintain consistent performance. The effect of replacing the sensor with a fixed resistor will be the opposite of what you intend.
Old 07-31-2013, 09:26 PM
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He's not the only LS guy I know talking about doing something like this.
Bracket racing is too competitive to be chancing the car to pick up on the big end as the night goes on.
Old 07-31-2013, 10:22 PM
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LS1 calibrations only pull timing at high intake air temps. They don't make air/ fuel changes due to IAT sensor input. Tuned properly they won't pull timing. You can not plug in a resister and prevent it picking up as the DA improves. You have to be smart enough to dial for it. That's why God made weather stations. :-)
Old 07-31-2013, 10:30 PM
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Originally Posted by Mighty Whitey
He's not the only LS guy I know talking about doing something like this.
Bracket racing is too competitive to be chancing the car to pick up on the big end as the night goes on.
Putting a resistor in is going to change more than the timing being pulled. The car uses it to calculate many other things.

If you want to get rid of or modify the timing being pulled, then you need to get a tuner and change the IAT table. I would not get rid of the timing pull though. If anything just pull more timing at lower temps to match what it is pulling at higher temps or tune your timing with that in mind. You may could play around with it to get it to pull more timing the better the weather gets in order to keep the car more consistent.

Old 07-31-2013, 11:32 PM
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Originally Posted by Ed Wright
LS1 calibrations only pull timing at high intake air temps. They don't make air/ fuel changes due to IAT sensor input. Tuned properly they won't pull timing. You can not plug in a resister and prevent it picking up as the DA improves. You have to be smart enough to dial for it. That's why God made weather stations. :-)
I was under the impression that the MAF and MAP use the input from the IAT.
Old 08-01-2013, 06:50 AM
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Originally Posted by brandonppr
I was under the impression that the MAF and MAP use the input from the IAT.
Nope. Some calibrations use it for P.E. fueling, that function is not enabled in any F or Y body LS1 calibration I have ever seen. It can be enables, and the corrosponding table populated.

The MAP sensor only reads Baro and once the engine is started, manifold vacuum vs Baro (MAP), independent of any other sensors.

MAF sensor, likewise, reads the mass of the air coming in the engine (not just CFM) independent of any other sensor. As the DA improves, the MAF sensor "tells" the PCM, thus the appropriate amount of fuel is added.

What sharp Stock, SS and bracket racers do to make the car change less with the weather, thus easier to dial, is run the car on the lean side. It likes cool air less, minds hot air less. Mine is quicker at 12.8-1, in "bracket mode" I run it about 13.2-1.
Old 08-01-2013, 07:26 AM
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I see why you want to do it. We deal with a lot of bracket cars. I've seen inlet temp hit 190 degree's in the staging lanes from heat soak.

For my car when I bracket raced it for 11.5 class and 10.5 class we put the sensor in the front bumper near the license plate so it only reads outside air temp. No more stupid high temp readings in the lanes. Helped a lot dialing in the car to run the number every race.
Old 08-01-2013, 08:13 AM
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All you have to do it take the spark retard out of that table. Smart people open the hood in the staging lanes to lessen heat soak. Some of you guys need to go to an NHRA race sometime and pay attention in the pits and lanes.
Old 08-01-2013, 08:25 AM
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Good info Ed

I have my IAT dangling in front of the filter. It reads the actual outside temp because the fan is always pulling air past it. I did that to get rid of the heat soak because the plastic still gets hot from the engine, but going down the track, it is getting cool air.

We run evening races which usually means we get faster all night. I am on SD tune. I generally run .00-.01 different between passes. I usually just dial it .01 down from the last run.
Old 08-01-2013, 09:36 AM
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So with a SD tune, do you need to put the IAT at the front bumper area.
And not at the TB.
Old 08-01-2013, 10:47 AM
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Originally Posted by RENE'S RAGE
So with a SD tune, do you need to put the IAT at the front bumper area.
And not at the TB.
I don't think it will really matter. I have mine there because it goes up and down depending on how much time between runs and sitting in the lanes.



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