Real IAT Mod Kia stinger gt 3.3t

[7thSonEngineering]

Car: Kia Stinger Gt AWD 2019
Ambient temp: 33f
Weather: Snowing
Date: 12/21/2024
Time: 4:16am - 4:38am
Purpose: Testing potential mod
Mod Name: IAT sensor relocation kit (prototype)
For sale name: Kia stinger Gt Real IAT ( Jan 2025 release ebay)
Car Mods: BMS BEF, Takeda intakes, Megan secondary downpipes

The purpose of this post is to investigate whether relocating the Tmap (temperature + mass air pressure) sensor increases the Hp and torque on a kia stinger or any other vehicle with this motor ( 3.3t). Why would someone want to relocate the Tmap sensor you ask? Because the Tmap sensor is attached to the intake manifold which heat soaks and this effects the minimum IAT the the engine will see. This effects timing, HP, TQ and Mpg. Typically the IAT sits between 20-40f above ambient.

The relocated location of the tmap sensor is actually the stock location for the map sensor on this motor. The Tmap sensor is located behind the throttle body (figure 1) and the map sensor is located on the charge pipe before the throttle body (figure 2)


(figure 1)

(Figure 2)

So the Map sensor and Tmap sensors swap places. This makes this Mod completable in 5 minutes with my sensor relocation cable.

Lets get onto the prototype installation pictures.







Now beings the road test. Notice the Time in the top left hand corner of the screen shots.

Time: 4:16am - The temperature ambient temperature was 33f this screen shot is post pull (50mph -120mph). Notice that my lowest IAT (intake Air Temperature) temps were 39.2f. The peak IAT Temps were 48.2f. (Hp and torque numbers are estimated by the app)


Time 4:21am - I Pulled over on the side of the highway and removed the mod. Reset the app values and this is what the IAT temp shot to 60.8f. So now that I'm back to stock I will do another pull (next pic)



Time 4:22am- Notice the peak HP and Torque numbers (estimated) and compare them to the picture at 4:16am. (54-130mph pull). Also note that with the sensor relocation mod the boost levels are lower (idk why)


Time 4:31am - I pulled back over and reinstalled the mod got back on the highway and did a pull 111mph top speed (remember it was snowing).



Time 4:32am- Just cruising along and letting temps drop to see where they fall back down to.


Time 4:38am- Driving on the highway and checking to see if my mpg increases. Notice my min & max speed and also how low the IAT temps have dropped.

This finishes my testing for today and my thoughts on this mod are. More low end power in terms of just driving around, Better mpg (seemingly) and the car accelerates faster when I step on it.

The estimated HP and Torque numbers above:
Pull 1 (modded) : 421hp 470ftlb
Pull 2 (stock) : 414hp 429ftlb
Pull 3 (modded): 426hp 488ftlb

So estimated hp and torque gains of
7-12hp
41-59 ftlb

Not bad for a 5 minute mod.

 

[BIG-D]

I love you

Wanna have my babies ?

I have data with engine cover on and off, wanna see it ??

IAT'S are quite surprising , especially once you delete the coolant flowing into the TB.

 

[Thomby]

This finishes my testing for today and my thoughts on this mod are. More low end power in terms of just driving around, Better mpg (seemingly) and the car accelerates faster when I step on it.

I'm skeptical of these estimates, both power/torque (which may just take temp as a formula input) and instantaneous mileage. Is your theory that the TMAP is measuring artificially high temperatures due to the manifold's heat soak? Or are you just feeding an artificially lower temp to the computer?

If it's the latter, there used to be tons of ebay "tuner chips" that were basically resistors pegging temp readings at minimum to trick your ECU, and didn't actually make your car run any better. At minimum I think you'd want to track mileage for a full tank before/after, and do a dyno run.

IAT'S are quite surprising , especially once you delete the coolant flowing into the TB.

Now this I could see having a beneficial effect, because you're actually lowering the intake charge temp vs. manipulating the reading. Do you have any pictures/writeup?

I've had older cars where TB coolant line removal was a popular mod, both for performance and to simplify the engine bay & reduce potential leaks. I've read that it's to keep the throttle from potentially freezing & sticking in extremely cold conditions, but I don't see a realistic risk given the proximity to the hot engine.

Other answer I've seen is to make the intake charge more consistent (since coolant temp is controlled), but I don't like that answer either as it seems like it would heat the intake air 100% of the time.

 

[7thSonEngineering]

I'm skeptical of these estimates, both power/torque (which may just take temp as a formula input) and instantaneous mileage. Is your theory that the TMAP is measuring artificially high temperatures due to the manifold's heat soak? Or are you just feeding an artificially lower temp to the computer?

If it's the latter, there used to be tons of ebay "tuner chips" that were basically resistors pegging temp readings at minimum to trick your ECU, and didn't actually make your car run any better. At minimum I think you'd want to track mileage for a full tank before/after, and do a dyno run.


Now this I could see having a beneficial effect, because you're actually lowering the intake charge temp vs. manipulating the reading. Do you have any pictures/writeup?

I've had older cars where TB coolant line removal was a popular mod, both for performance and to simplify the engine bay & reduce potential leaks. I've read that it's to keep the throttle from potentially freezing & sticking in extremely cold conditions, but I don't see a realistic risk given the proximity to the hot engine.

Other answer I've seen is to make the intake charge more consistent (since coolant temp is controlled), but I don't like that answer either as it seems like it would heat the intake air 100% of the time.

The estimates are crank hp & torque. So perhaps 390whp 440ftlb

Yes my theory is that since the tmap sensor sits in the intake manifold that sits on the engine it will heat up more than a tmap sensor located on the aluminum charge pipe. The temperature being registered is the temperature of the actual air moving through the charge pipes.

Those eBay “tuner” chips would throw a code because the ECU compares the ambient temp sensors voltage outputs to the Tmaps output.

The coolant running through the throttle body is to keep the throttle plate from sticking. It may heat up the air a little bit but not much. It can and should be bypassed if your car doesn’t experience extremely low temperatures

 

[7thSonEngineering]

I love you

Wanna have my babies ?

I have data with engine cover on and off, wanna see it ??

IAT'S are quite surprising , especially once you delete the coolant flowing into the TB.

Lol no to the babies

How much did taking the engine cover off effect the temperature ??

 

[Thomby]

The estimates are crank hp & torque. So perhaps 390whp 440ftlb

I'm not arguing with the actual values, I'm saying the car doesn't have a dyno to directly measure them, it's an estimate based on air, fuel, and maybe temp & timing. So when you feed it a lower temp signal and it shows you a higher power estimate, it's not really confirming anything, it may just be saying "my lookup table says 10 degrees lower should be 15 more horsepower".

Yes my theory is that since the tmap sensor sits in the intake manifold that sits on the engine it will heat up more than a tmap sensor located on the aluminum charge pipe. The temperature being registered is the temperature of the actual air moving through the charge pipes.

Ok but do you think the air in the intake manifold is actually cooler than the TMAP/manifold, and stock Stingers are always seeing an artificially high temp? Or is it also heated by the manifold and you're just feeding it a lower upstream temp?

If you tell the car the air is cooler (denser), I assume AFR won't change (or it will briefly increase fuel then correct when O2 sensors show rich), so the other variable likely to change is timing advance (cooler charge means more room for advance). If the air entering the engine isn't actually cooler, then you're just moving closer to spark knock...probably fine during low load cruising since you aren't knock limited, but under load it shouldn't gain you anything.

 

[7thSonEngineering]

I'm not arguing with the actual values, I'm saying the car doesn't have a dyno to directly measure them, it's an estimate based on air, fuel, and maybe temp & timing. So when you feed it a lower temp signal and it shows you a higher power estimate, it's not really confirming anything, it may just be saying "my lookup table says 10 degrees lower should be 15 more horsepower".


Ok but do you think the air in the intake manifold is actually cooler than the TMAP/manifold, and stock Stingers are always seeing an artificially high temp? Or is it also heated by the manifold and you're just feeding it a lower upstream temp?

If you tell the car the air is cooler (denser), I assume AFR won't change (or it will briefly increase fuel then correct when O2 sensors show rich), so the other variable likely to change is timing advance (cooler charge means more room for advance). If the air entering the engine isn't actually cooler, then you're just moving closer to spark knock...probably fine during low load cruising since you aren't knock limited, but under load it shouldn't gain you anything.

i don’t know the actual power numbers the car is making. All that app estimate does is let’s me compare estimates to see if there was an actual change since all other variables are the same besides the “mod”

So yes it actually does something but how much does it actually do ? Idk


Stock stingers are seeing artificially high temperatures. Any vehicle with the tmap sensor on the intake manifold will see artificially higher temps.

The air moving into the engine isn’t actually cooler. But the tmap sensor will be reading a more “real” air temperature value because it’s not being impacted by heat soak of the manifold. This in turn will change the timing/temp table value and the ECU will add timing which increases power. The car will run better from idle to redline


Let’s say without the mod the tmap sensor reading is 70f on a 40f day. The driver steps on the gas the timing tables are looking at the 70f temp. And making power based upon that. Since the intake manifold is already heat soaked to 70f the tmap sensor will never register a temperature below 70f.

Let’s say a Real iat modded stinger is the one racing the stock one. The same 70f ambient temp but the tmap sensor in the modded stinger is reading 52f. The modded stinger will make more power until intake temps match the stock stinger.

If the temps don’t equal until after 10 seconds WOT then the modded stinger is making more power over that 10 seconds.

 

[Thomby]

Stock stingers are seeing artificially high temperatures.
But the tmap sensor will be reading a more “real” air temperature value because it’s not being impacted by heat soak of the manifold.

Ok, gotcha. You're saying that incoming air isn't spending enough time in the manifold to pick its heat up, and that the TMAP is measuring itself (at manifold temp) more than it's measuring the actual air flowing by.

I still think running a full tank with and then without the modification would be a good test (as would before/after dynos, but testing mileage should be easier).

 

[7thSonEngineering]

Ok, gotcha. You're saying that incoming air isn't spending enough time in the manifold to pick its heat up, and that the TMAP is measuring itself (at manifold temp) more than it's measuring the actual air flowing by.

I still think running a full tank with and then without the modification would be a good test (as would before/after dynos, but testing mileage should be easier).

Exactly. I’ll be leaving this mod on for the next few weeks and watching my range per full tank of gas.

 

[STINGER]

Interesting, nice mod, looking forward to the long term results

 

[AWDGT2]

Install one of my phenolic 1" spacers between the upper and lower intake. I guarantee another 10 degrees drop. I cruise around now at about 10 degrees above ambient.
3.3 tt Spacer

 

[7thSonEngineering]

Install one of my phenolic 1" spacers between the upper and lower intake. I guarantee another 10 degrees drop. I cruise around now at about 10 degrees above ambient.
3.3 tt Spacer

Iv seen your spacer. Lower intake temp reading will give anyone the same results whether it’s the spacer or a tmap sensor relocation.

Wonder what the combination of both would do ?

 

[Baluchitherium4]

I love you

Wanna have my babies ?

I have data with engine cover on and off, wanna see it ??

IAT'S are quite surprising , especially once you delete the coolant flowing into the TB.

I'm very interested in seeing your testing results from the engine cover being off and the tb coolant flow bypassed.

Post em' up!

 

[Baluchitherium4]

Install one of my phenolic 1" spacers between the upper and lower intake. I guarantee another 10 degrees drop. I cruise around now at about 10 degrees above ambient.
3.3 tt Spacer

Do these spacers come predilled with gaskets and longer bolts? Can you put a link to the spacer?

 

[7thSonEngineering]

Do these spacers come predilled with gaskets and longer bolts? Can you put a link to the spacer?

1" Phenolic Spacer for the Kia Stinger 3.3tt

This 1" Phenolic material separates the upper intake and the lower intake. The kit comes with 8 stainless steel bolts with washers and a pre cut gasket. Please read the note below before ordering. This spacer can lower you IAT temperatures by raising it off the lower where all the heat is...

stingertop20.com

 

[7thSonEngineering]

More testing

1200seconds = 20 minutes
1800 seconds = 30 minutes

Speed limit: 55mph

Ambient temp - Intake air temp = 7.2f

What other mod gets intake temps this low ??

 

[robz32]

1" Phenolic Spacer for the Kia Stinger 3.3tt

This 1" Phenolic material separates the upper intake and the lower intake. The kit comes with 8 stainless steel bolts with washers and a pre cut gasket. Please read the note below before ordering. This spacer can lower you IAT temperatures by raising it off the lower where all the heat is...

stingertop20.com

Not in stock anymore

 

[jinthadell]

If I’m reading everything correctly, and please correct me if I’m wrong. What if you have a JB4 installed, couldn’t you just swap the inputs on the sensors and achieve the same results?

 

[7thSonEngineering]

If I’m reading everything correctly, and please correct me if I’m wrong. What if you have a JB4 installed, couldn’t you just swap the inputs on the sensors and achieve the same results?

No because the real ECU is still reading the original sensor locations temperature reading and that affects timing. You want the ECU and JB4 to read from the same location

 

[jinthadell]

I meant to specify only swapping the JB4 sensor “inputs”. And still plugging the “outputs” in the correct factory locations. Now you would have to break the loom on the JB4 harness to separate the wiring. From what I can tell IAT mod is just wiring to trick the car into reading temp at the charge pipe before the T/B and not the intake manifold after the T/B. Right or wrong?