GR Yaris In what range is your CAT's (charged air temperature) in GR Yaris when driving on track?

Michael Knight

Michael Knight

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for recent times noted that IAT's climb higher than I remember then being when I bought the car.

in my car IAT seems to be always +10'C above ambient. with cold car its in ambient, but after the car warms up it climbs to +10'C.
its strange as MAP sensor should get cold air (got the wagner inlet) + hood ducts.
Not that it would have big impact but still find it strange. IIRC it used to be closer to ambient in early years of ownership, but recent year or so it has been that +10'C.

When doing WOT runs on track the IAT decreases initially but not by much.
here's IAT data from last track session. Stock airbox and wagner airbox inlet.

Ambient 23'C
1st stint Start30'C
1st stint End40'C
2nd hot stint start36,6'C
2nd stint end42,7'C
3rd stint start37'C
3rd stint end41,7'C

I did measure with external thermometer the temps above the airbox last spring, and they were just 1-2'C above ambient under the hood, so I don't think hood underside temps get too high.

If you can share where your IAT's are when doing WOT runs it would be nice to compare.
I did these measurements on track where car stays on WOT constantly so road figures do not really compare.
 
Checked the data from hot track day (30'C) from August 2022.
Start temps 51.6'C,
peaked 41.6'C but dropped to 31'C when at WOT.

so all in all they were in ambient when running on WOT.
 
Michael Knight said:
for recent times noted that IAT's climb higher than I remember then being when I bought the car.

in my car IAT seems to be always +10'C above ambient. with cold car its in ambient, but after the car warms up it climbs to +10'C.
its strange as MAP sensor should get cold air (got the wagner inlet) + hood ducts.
Not that it would have big impact but still find it strange. IIRC it used to be closer to ambient in early years of ownership, but recent year or so it has been that +10'C.

When doing WOT runs on track the IAT decreases initially but not by much.
here's IAT data from last track session. Stock airbox and wagner airbox inlet.

Ambient 23'C
1st stint Start30'C
1st stint End40'C
2nd hot stint start36,6'C
2nd stint end42,7'C
3rd stint start37'C
3rd stint end41,7'C

I did measure with external thermometer the temps above the airbox last spring, and they were just 1-2'C above ambient under the hood, so I don't think hood underside temps get too high.

If you can share where your IAT's are when doing WOT runs it would be nice to compare.
I did these measurements on track where car stays on WOT constantly so road figures do not really compare.
Click to expand...
Some questions.
Your measuring at the MAF sensor/air filter housing?
The WOT runs are with the OEM filter housing and the flap open (plus 4000rpm) sucking hot air from the engine bay?
 
Sekred said:
Some questions.
Your measuring at the MAF sensor/air filter housing?
The WOT runs are with the OEM filter housing and the flap open (plus 4000rpm) sucking hot air from the engine bay?
Click to expand...
my own stupidity - its actually CAT post IC so from MAP sensors. So this explains better why air heats up to +10'C ambient after some driving.
But in that regards intake temps are ok. My audi peaks 50'C after one pull.. :D
 
Admins could edit the thread topic to CAT (Charged air Temperature) to clear out the confusion.
 
Michael Knight said:
my own stupidity - its actually CAT post IC so from MAP sensors. So this explains better why air heats up to +10'C ambient after some driving.
But in that regards intake temps are ok. My audi peaks 50'C after one pull.. :D
Click to expand...
Not that it matters much, but if you're using the standard PID (Mode 01, PID 0x77), you're most likely seeing the temperature from the pipe after the intercooler, not the one from the intake manifold MAP sensor.
 
tonic said:
Not that it matters much, but if you're using the standard PID (Mode 01, PID 0x77), you're most likely seeing the temperature from the pipe after the intercooler, not the one from the intake manifold MAP sensor.
Click to expand...
I'm not sure from where the temp is received as using aftermarket system where you cannot see spesific PID's but tested yesterday its not MAF. Assuming its the one MAP sensor in intake manifold.
 
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