Air Temp Relocation Kit

[32valvZ]

Is it worth the time to put one in? Any real advantages? Will the prom need recal again?

Thanks!

[lfalzarano]

Marc has a write up

http://www.zr1specialist.com/HAT%20W...r%20sensor.htm


Sent from my iPhone using ZR-1 Net Registry

[We Gone]

I have mine relocated to the air intake box as it passes over the radiator. Any results on how this effects or differs from mounting at the front of the vehicle ?

[-=Jeff=-]

I have the air temp relocation kit I will probably never use.. Let me know if you have interest and I can dig it out.. It is brand new

[XfireZ51]

If u relocate the MAT (Manifold Air Temp)to say the radiator shroud or somewhere else, you are “converting” it to an IAT (Intake Air Temp) sensor. This is done due to the heat soak of the sensor that occurs by the plenum and air horn. When u look at the calibration, there is a table that applies a correction factor to the fueling in order to compensate for the air temp and keep the fueling consistent. The table tells the ECM how much or the ratio the ECM should consider between Temp and Air Temp. When u move the sensor, that table is now incorrect. Looking at the values in that table, it assumes your typical operating temp range is going to be ~ 80-110C or so. Your now relocated sensor will NEVER see those temps. And so the ECM will adjust fueling based on what are much lower temps using those adjustment numbers, ie motor will run richer.
So, in order for the now IAT to properly provide more accurate input to the ECM,
that table needs to be modified for the temp values the ECM will be seeing from the IAT. That means, as in my case, the ECM will see temps down in the 8-40C range typically. So the values there need to be changed in order for the ECM to properly compensate for intake air temps.
Could u adjust VE tables instead to compensate? Yes, but the minute the intake air temp varies from the one u used in adjusting the VE table, the fueling will be off.
The intent of this compensation is to apply a factor to the base VE table taking into account now the temp of the air. Why? Because the correct fuel is based on the mass of the air the motor is taking in, which temp affects.
As air temp changes, air mass changes, and so amount of fuel must be adjusted for that mass.
You can see this as u sit at idle and intake air temp rises. The key is to have ur compensation table set up so u continue to record a consistent BLM as intake air temp varies.
Bottom line, no sense moving MAT unless u modify the compensation table, IMO.

[WARP TEN]

I don't know if Marc alters the tables, Dom, but I do know that one of the first modifications I did on the '93 was to move the sensor to the plastic part above the air filter. On the '95 Marc moved it to his preferred location in front of the radiator. He says the higher temps cause the engine to pull spark, costing about 10 HP and 10 ft lbs TQ. I am not sure I could tell the effect of changing the location but it always seemed sensible to me based on info I had at the time. --Bob

[We Gone]

Marc made the adjustments to the tables with mine located to the plastic part above the air filter.

My question for anyone who knows>

I have mine relocated to the air intake box as it passes over the radiator. Any results on how this effects or differs from mounting at the front of the vehicle ?

[XfireZ51]

Originally Posted by We Gone

Marc made the adjustments to the tables with mine located to the plastic part above the air filter.

My question for anyone who knows>

I have mine relocated to the air intake box as it passes over the radiator. Any results on how this effects or differs from mounting at the front of the vehicle ?

That’s where mine is located also. And yes the sensor does affect timing, throttling it back as temps rise.
I have mine in the same spot so that it more accurately mimics the intake air temp as the motor sits there for instance during idle. When I datalog I can track the change in intake air temp w that used for outside air temp indicator on the AC controller.

[Paul Workman]

Well, here's a twist for the dicussion: Coolant bypass affect on the air temp sensor located in the stock position.

Case in point, after bypassing the TB, coolant does not heat the TB and the horn directly in front of the TB. In fact, you can lay your palm on the plenum with the engine running and it is quite cool w/o the coolant running through the TB.


Thoughts on that, Marc or Dom?? Does bypassing the TB make moving the sensor unnecessary??

Off Topic, but also related to plenum temp: Consider the affect the cooler plenum temp has on the critical DIS module and its life expectancy, being that it is heat syc'ed to the plenum...

[XfireZ51]

Originally Posted by Paul Workman

Well, here's a twist for the dicussion: Coolant bypass affect on the air temp sensor located in the stock position.

Case in point, after bypassing the TB, coolant does not heat the TB and the horn directly in front of the TB. In fact, you can lay your palm on the plenum with the engine running and it is quite cool w/o the coolant running through the TB.


Thoughts on that, Marc or Dom?? Does bypassing the TB make moving the sensor unnecessary??

Off Topic, but also related to plenum temp: Consider the affect the cooler plenum temp has on the critical DIS module and its life expectancy, being that it is heat syc'ed to the plenum...

Paul,

IIRC, the coolant thru the TB was for icing in cold weather. Relocated MAT sensor will typically see air temps in the 15-40C range which isn't close to the coolant operating temps of 80C+ w a stock therm. And I seriously doubt the TB is as cool as 15-40C at operating temps.