IAT- when to upgrade the intercooler?

[MetalMania80]

Hi. When the temperature is too high?

I know lower is better, but not going to madness, when you can say that your boost is limited by IAT?

Is there a magic number?

 

[oddball]

No.
Aftermarket intercoolers will resist heat soak "more" than the stock. That means you can run at WOT longer before the intercooler can't cool any more, or can make more laps on a track before it gets heat soaked.
A bigger intercooler doesn't necessarily mean "lower" IAT, like "I was cruising on the highway with IAT of 110, put in new intercooler and now it's 60!". You're unlikely to see a noticeable change in any kind of normal driving.

They don't cool "lower", they cool "for longer".

 

[MetalMania80]

Thanks for the replay.

So for normal driving, not racing, there is no need for replacing the intercooler?

 

[oddball]

Right. Only if you think it's fun/pretty/whatever. I have a JT intercooler just because I wanted one. I know it doesn't actually DO anything for me.

 

[Edwardo]

So the IAT measures post intercooler. Is there any pre turbo measurement?

 

[MetalMania80]

I thought about BMS Intercooler to have easy access to install CPI, but now I have ordered EK1 and maybe I upgrade the fuel pump, so no CPI.

You saved my money!

 

[ExtremePowerHouse - MIke]

i recommend upgrading the intercooler if the car is tuned. if you are keeping it stock and you dont drive hard, there is no need to upgrade the intercooler

 

[7thSonEngineering]

Consider this.

Thread 'Real IAT Mod Kia stinger gt 3.3t'

Dec 21, 2024

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...

• 7thSonEngineering
• Replies: 202
• Forum: Engine, Drivetrain, Intake, Exhaust Discussion

• 

 

[Thomby]

So for normal driving, not racing, there is no need for replacing the intercooler?

Depends what you mean by "normal driving". Even driving aggressively on the street at higher maps, it's hard to spend very much time in boost, and the times you are at WOT you're getting a ton of airflow to carry away heat. I haven't seen either wild IATs or timing corrections in my logs even on Map 5 in summer, so I haven't pulled the trigger on an intercooler.

What I do notice is that sitting with the engine running (in the drive through line, waiting for a train, running the engine in a parking lot) will skyrocket IATs even at idle. It drops once I get moving but there has to be some degree of heat soak for the radiator, intercooler, and everything under hood. I suspect for street use the biggest benefit from a larger intercooler may be a quicker return to near-ambient IATs once the car starts moving (and maybe a slower rise in temp due to more thermal mass).

 

[BIG-D]

Exactly... car is more responsive tho' with factory intercooler of course.

 

[Retro7610]

Right. Only if you think it's fun/pretty/whatever. I have a JT intercooler just because I wanted one. I know it doesn't actually DO anything for me.

Very interesting. But does having a higher capacity intercooler increase turbo lag? That's been my worry.

 

[BIG-D]

That was my belief but I am now on my 3rd set of tyres so it isn't an issue at all.

 

[G-434364]

So good to know! Though I don't track mine, I love to do.long hard extra legal pulls at every opportunity and also sitting waiting on traffic frequently. Perhaps a.higher capacity intercooler is for me too.

 

[Thomby]

Very interesting. But does having a higher capacity intercooler increase turbo lag? That's been my worry.

I've read this anecdotally, but engine/turbo airflow is so great that the incremental volume will fill in a fraction of a second. If you ask ChatGPT or Claude, they guesstimate the extra volume takes an additional 10-50ms to pressurize.

Claude even wrote a small program taking displacement, boost, rpm, and intercooler sizes as input parameters, with sample values from the N54, STI, etc. (Its first attempt actually predicted 12-1400ms in the program vs. 10-40 via text, and when I asked it, it found some bad cubic inches / CFM unit conversions and fixed it, so you'd probably want to sanity check its airflow assumptions etc).

 

[MetalMania80]

You can ask AI when to consider that the intercooler is not doing well, at what the IAT-external temperature difference.

Best for low IAT is WMI

 

[Retro7610]

Thank you very much, Thomby, Big-D, et. al. This conversation is an eye opener for me, not having much experience. I now know I'm overheating my GT2. I do intend to tune the car soon and am trying to maintain my warranty where possible. I have an Eibach Pro suspension upgrade, catch cans, the VT Snorkels and K&N intakes, Throttle Commander and run with Driven DI oil for lower evaporation. Knowing the benefits and minimal turbo lag downside, which one would you men recommend?
Thanks again.

 

[MetalMania80]

"I now know I'm overheating my GT2" How do you know that?

 

[Retro7610]

Overheat is the wrong term. Based on this conversation and the way I drive, as Thomby indicated, with a larger intercooler I might see a "quicker return to near-ambient IATs once the car starts moving (and maybe a slower rise in temp due to more thermal mass)". Quicker recovery to loert IATs would see to indicate longer engine life which is what I'm after.

 

[MetalMania80]

"Quicker recovery to loert IATs would see to indicate longer engine life which is what I'm after."
"I do intend to tune the car soon and am trying to maintain my warranty where possible. I have an Eibach Pro suspension upgrade, catch cans, the VT Snorkels and K&N intakes, Throttle Commander and run with Driven DI oil for lower evaporation."

If you want longevity, stay stock.

IAT makes a difference when you use aggressive tuning and race. Lower IAT helps to prevent knocking. That's all.

When at full boost, you see IAT-ambient > 60-140 F, that means you need a bigger intercooler.

 

[G-73408]

Thanks for thr clarification!