Yes approx the same of me, and when I hard pull >270 to 320 by 22/24°C AT my IAT reaches 55°C, I think it is not a really an Ics issue, that's like that we can't expect consistent high perfs by warm AT...
I logged 2 friend's cars with AM Ics, they are worst with lower boost...

 

It will help to the EGT too. The cooler the air inside the motor, the cooler it gets out from your exhaust

 

You need to check your PM's...lol. I've got a proposition for you.

 

I tested a few AT last hours...

-22°C AT: IAT 55°C and time pulling end 5th, 100-200 6.3'
-26°C AT: IAT 55°C and time pulling mid 5th, 100-200 6.4'
-18°C AT: IAT 42°C no time pulling end 5th (didn't tryed 6th), 100-200 6.2 and far more consistent power.

I tested with my buddy's bone stock 997.1TT (6spd as mine), his car spools about 300rpm earlier, have good torque untill 4000 and seems flat after 4000; mine is a bit flater before 4000 and blast it from 4000 to 7000; upgraded VTGs...

 

This is some good practical data. Seems like you are getting very consistent results with your set-up. So it appears best to stay under 20 C (68 F) for these kinds of pulls with .2 IC? That's an eye opener. Thanks for testing and posting Pascal.

 

Well did not log in for a while and I see this thread is going deep into the subject.
A few clarifications on my side if it helps.
The experiment with skandalis was with exact same parts apart from coolers. Ie I had changed to the latest at the time exhaust sensor and also changed mafs. The only diff was the ics.
My car exhibited a big difference with the new exhaust sensors as the old ones were obviously misreading egts and confusing the ecu. Hint; That's why p changed the part 5 times already! The difference is that with my setup with the expansion intake I get a burst of power from 6500 to 7800rpm and before the change the car would be sluggish 8/10 times at that rpm range. After I changed power came back. Indicatively I was logging low to mid 6s 100-200 before changing those sensors. After the change (also changed mafs and a dirty fuel filter) the car started doing mid and low 5s. Needless to say that I advise people to look into this as one can lose power quietly without realising why with those sensors..
Now when we tried the new ics 2 weeks later the performance moved on as documented by the other thread. One can notice that I still started losing power at certain point as the lambda started getting richer at high speeds most definitely because of egts. The durametric does not show the actual reading but only modelled so mine was still showing 855 or sth while my tuner logged higher values on the dyne runs.
Now about a month ago I did another dyno calibration with these coolers and my tuner was quite impressed with the efficiency of those coolers and they got 740hp at 25+ ambient while the previous was 735 at 5 ambient. That is avert big difference, I would say around 20 or maybe 30hp on similar conditions. But the real difference is that with these coolers the power consistency is just on a different league (before I was quite disappointed on that front).
Re k24 quest for power with VTgs on a stock engine my experience is that it is very difficult to get more than 670hp with this setup. I know that in all forums we hear crazy numbers with stock engines and VTgs but my experience is that until we opened the engine to free those cylinder heads with cams and porting, the cylinder pressure was too high to get over these levels. And that was with exhaust with almost 0 back pressure and also expansion intake. More specifically those VTGs are heating up too much and the small turbine side has too much back pressure for more power. Already I am being told from reputable European tuners that they don't believe it is possible to get beyond 680hp with my setup (ie they don't even believe my measurements).
If you notice with my setup power comes really from very high ignition timing and not boost. (because the expansion intake cools IATs but also reduces boost). At high rpm I am running 1.4 bar which is not a lot considering. Downside is that it's is very dependant on temps and fuel quality. Also very difficult to tune. And it did not work properly until I switched to those .2 ics really.

 

Was there something wrong with your original mafs? You have modded GT2 hotside vtg turbos, right? So JUST by changing the sensor your times went from low-mid 6s to mid-low 5s???? WOW

 

Oh, how much is the sensor? Any idea what the part number is?

 

so which coolers are best beside ctr's and secans and mine of course ?

I talked with my tuner he said 997.2 coolers are fine up to 650PS.

 

The part number is 99760625005 (this started as 001 for first 2007 cars). Costs around 670 euros I think.
In my car I eventually got a exhaust sensor fault and then I changed but the symptoms and performance issues were present way before I got the fault so I am sure now that they were not working properly for a looong time.
My vtgs have 49.8mm compressor side, the turbine side is only cut back for flow. I don't know anyone who has managed to convert the turbine hot side- this is the restriction. These to my knowledge are the biggest ones available by any european tuner. (I don't understand how on can get 68m without changing the hot side as the ratio of both wheels is already not ideal with my setup).
The mafs were changed after I had a filling with very bad fuel (greece...) and had to change spark plugs, fuel filter and also changed the mafs as a maintenance item (at 45k kms not a bad idea).
Karol I think we demonstrated conclusively that the .2rs coolers can handle more than 650 or 700hp with my measurements. Its not possible to get those times with less that the power quoted.
However as I was trying to say above all these mods try to work around the problem that there is just too much backpressure from those small turbines which results into backpressure and heat in the cylinder heads at those power levels. And I am talking about 20secs+ at WOT. Not just short 5-8 second bursts with plenty of time in between to cool things down.

 

Thanks for that. But your vtgs have the GT2 hotside, right? Were you able to compare the tt and GT2 hotside?