Intake Air Temperature Readings

S3_Sanni

Active Member
VCDS Map User
What are the intake temperature readings you guys have on full boost?
I have a peron intercooler fitted and the most i see is 42 degrees. Been told it should be less than 30 if that. Could anyone confirm?
 

Mario8P

Registered User
What are the intake temperature readings you guys have on full boost?
I have a peron intercooler fitted and the most i see is 42 degrees. Been told it should be less than 30 if that. Could anyone confirm?
It all depends on ambient temperature mate. And if you where driving in a stop and go situations thatll also raise your temps.

For example in our climate when temps are at around 26-28 Celsius my IAT are around 35-40 while cruising. but when I go WOT temps reach about 24-27c.
Keep in mind my water methanol helps in dropping the temps on WOT.
 

S3_Sanni

Active Member
VCDS Map User
It all depends on ambient temperature mate. And if you where driving in a stop and go situations thatll also raise your temps.

For example in our climate when temps are at around 26-28 Celsius my IAT are around 35-40 while cruising. but when I go WOT temps reach about 24-27c.
Keep in mind my water methanol helps in dropping the temps on WOT.
Cruising it reads around 20ish Mario. However on full WOT it reads over 30+.. Most the time the reading goes into the 40s. Ambient temp around here at time i checked was between 14-15 degrees...

What were your IAT readings before Water meth?
 

S3Alex

Rarely neutral
Gold Supporter
Cruising it reads around 20ish Mario. However on full WOT it reads over 30+.. Most the time the reading goes into the 40s. Ambient temp around here at time i checked was between 14-15 degrees...

What were your IAT readings before Water meth?

Even without the WMI running,mine(a ProAlloy) never gets anywhere near those sorts of temps.
 

S3_Sanni

Active Member
VCDS Map User
Even without the WMI running,mine(a ProAlloy) never gets anywhere near those sorts of temps.
Alex, any idea what can cause the temp to be so high??
I have some slight damage on my ac rad at the bottom but could that really have a big effect on IAT like mine?
 

Mario8P

Registered User
Cruising it reads around 20ish Mario. However on full WOT it reads over 30+.. Most the time the reading goes into the 40s. Ambient temp around here at time i checked was between 14-15 degrees...

What were your IAT readings before Water meth?

To be honest i never checked the IAT before sorry.

Alex, any idea what can cause the temp to be so high??
I have some slight damage on my ac rad at the bottom but could that really have a big effect on IAT like mine?[/QUOTE


I highly doubt that the AC rad damage can affect your IAT by any means.
 

Flexiblemouse

Registered User
When driving normally my temperatures are 4-5 degrees over ambient, on a full throttle pull to redline it will go up another 5 degrees or so.
 

S3Alex

Rarely neutral
Gold Supporter
There may be a number of reasons behind it,but something doesn't sound right.

If there's any obstruction to either airflow to the I/c,or restrictions in the piping,then cooling may be lost,but it's difficult to say whether or not that's the case.
I can only go from the I/c in mine,which never goes more than a few degrees above ambient,even on a full throttle drag.
 

S3_Sanni

Active Member
VCDS Map User
Thanks for the reply guys.
42 isnt much but for an upgraded intercooler it seems to much. Shouldn't be going over 30 especially with ambient temps being around 14.
Alex what AIT Readings do you get on yours?
 

Flexiblemouse

Registered User
Looks alright to me, you didn't say which turbo you had or how much power but it looks like the intercooler is a little undersized for your application.
 

S3_Sanni

Active Member
VCDS Map User
Sorry mate its an s3 8p3 ko4 turbo.. Running revo stage 2+
The intercooler i have is peron which is meant to be good?
 

Flexiblemouse

Registered User
I don't think that the temperatures are that bad considering you are pushing the k04 fairly hard and you are not using wmi.

If you want are worried and want suggestions:

Make sure the intake air is coming in from outside, not the engine bay.

Use a bigger turbo and run less boost.

Use a WMI kit.
 
Last edited:

nooone

Registered User
If the turbo is being run outside of its efficiency map, you get a little more power and a lot more heat.

I wouldn't worry, but you could talk to Revo about dropping the boost a psi or 2.
 

S3_Sanni

Active Member
VCDS Map User
So i dropped boost down from 8 to 7.. However still no difference.. Ambient temp was 10 degrees during time of logging.. AIT still read 40 on full boost.. Since it didn't make a difference i just put the boost back up to 8

https://www.dropbox.com/s/xa3hqytkarxbe6q/IAT B7.CSV?dl=0

Went out with a friend and did some logging in his car as well with his upgraded intercooler. On full boost his IAT did not go over 20 even when pushing the car.

Been told to try change ac rad to see if that solves it as mine has a little damage. Could anyone confirm?
 

Flexiblemouse

Registered User
I can't see what possible effect the condenser could have on your intake temperature, unless the damage extends to the intercooler.
 

S3_Sanni

Active Member
VCDS Map User
Yeah different set ups will result in different results.. But was just curious to know why mine was reading high compared to others..

Another friends s3 running stage 2+, however he has custom map and a airtec stage 2 intercooler, his is also half of what mine is reading

Regards to the ac rad fins.. Ive attached some pics.. Im not too good with these sort of things and knowing if this could be the problem so let me know what you guys think...

dc29c2b62d432879b1d679e90ba6ec30.jpg


76ddd5a4f32aade085f9add4d74a4981.jpg
 

nluk100

Registered User
Alex, any idea what can cause the temp to be so high??
I have some slight damage on my ac rad at the bottom but could that really have a big effect on IAT like mine?

What sort of boost are you running on your car? If you're raping the turbo then you will see higher IAT's. Can you log your EGT temp?

My car is running the std S3 alloy IC and it never saw more than +10deg over the ambient (outside) temp, even after 10 full runs on the dyno - that's why I've reach the conclusion that for stage2+ at least there is no point in going for anything bigger in the UK for fast road work.
 

S3_Sanni

Active Member
VCDS Map User
What sort of boost are you running on your car? If you're raping the turbo then you will see higher IAT's. Can you log your EGT temp?

My car is running the std S3 alloy IC and it never saw more than +10deg over the ambient (outside) temp, even after 10 full runs on the dyno - that's why I've reach the conclusion that for stage2+ at least there is no point in going for anything bigger in the UK for fast road work.
Im running back on boost 8.. Run boost around 1.6 peaks.. Then around 1.5.. and top end it tails down
Which block do i use to log egt?
 

Mario8P

Registered User
Am afraid there are no stock EGT sensor to log from
 

Flexiblemouse

Registered User
I think the condenser is a red herring. If the intercooler was badly damaged you would have a huge boost leak. The only feasible way the condenser could be affecting the intake temperatures is if it is restricting the airflow to the intercooler because all the fins are flattened, or part of the splash tray had become dislodged and is disrupting the airflow at the front of the engine bay.

I think the most likely scenario is that the intercooler is undamaged and working properly, but you have over estimated it's performance. Your K04 is not going to be very efficient at these power levels, and will be putting out a LOT of heat.
 

S3_Sanni

Active Member
VCDS Map User
I think the condenser is a red herring. If the intercooler was badly damaged you would have a huge boost leak. The only feasible way the condenser could be affecting the intake temperatures is if it is restricting the airflow to the intercooler because all the fins are flattened, or part of the splash tray had become dislodged and is disrupting the airflow at the front of the engine bay.

I think the most likely scenario is that the intercooler is undamaged and working properly, but you have over estimated it's performance. Your K04 is not going to be very efficient at these power levels, and will be putting out a LOT of heat.
I just bought an upgraded intercooler to keep the temps down during hard runs. The only thing im thinking of is a friend running airtec on his s3 with temps below 20.
Another with gti forge intercooler less than 20 too.
When i look at the ac rad fins through the bottom of the grill the whole bottom row of the fins looks damaged. So the air could be restricted and not working properly from the bottom? Changing that may hopefully help?
 

Flexiblemouse

Registered User
I really don't think it will make a difference if you change the condenser. I think you would be better off with either wmi or a larger turbocharger operating within a more efficient range for the same power.
 

nluk100

Registered User
Just so you know, it's not possible for your friends IATs to be below 20 deg if the outside temp is 20 deg. What they need to tell you is how much above the ambient (outside) air temperature they see after a few hard runs, normally you will see 10 - 20 deg above ambient. The standard (alloy, not plastic end caps) S3 IC showed 10 deg above ambient after quite a number of dyno runs on my own car.
 

S3_Sanni

Active Member
VCDS Map User
Just so you know, it's not possible for your friends IATs to be below 20 deg if the outside temp is 20 deg. What they need to tell you is how much above the ambient (outside) air temperature they see after a few hard runs, normally you will see 10 - 20 deg above ambient. The standard (alloy, not plastic end caps) S3 IC showed 10 deg above ambient after quite a number of dyno runs on my own car.
The ambient was 10 degrees pal not 20 degrees.. When cruising it was reading 19-10... Full boost his iat was to 13 wish is pretty good.. I can show you the log as well if you like?
I really don't think it will make a difference if you change the condenser. I think you would be better off with either wmi or a larger turbocharger operating within a more efficient range for the same power.
How much would wmi cost and would it really make a big difference?
 

DriverN00B

Registered User
I don't think going towards WMI is a solution to Sanni's issue. He's running stage 2+ ~330bhp with all the recommended hardware, just like tonnes of other stage 2+ s3's on these forums. Any remap should be tailored to the cars hardware and not the other way round. Similarly my GTi is running forge twintake and twintercooler, tbe but no upgraded hpfp. My map should be setup to run to the limitations of my weakest part (the stock hpfp) and not maxed to my strongest part. Every good mapper should be applying maps within the limitations of your hardware, it's clear from the majority that IAT's should be staying well clear of ambient +30. I'd like to see what @lvsracing have to say since Pat worked on the car... The increasing popularity of self-logging means that good afterpurchase service is what will distinguish the good from the bad.
 

S3_Sanni

Active Member
VCDS Map User
Can anyone with airtec stage 2 intercooler comment and tell me what intake temperature reading they get under full boost?
 
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