[johan]

For us that have tuned our cars it looks like the intercooler aint good enough under heavy use.
How big of a operation would it be to change, if there was a replacement to find?
Is it even possible to sacrifice the third rad for a front mounted intercooler (an extra pump would be needed i guess)

 

[Lelandjt]

Definitely not possible to do a front mount, too much piping. If that GT4 side scoop or similar is added to pull more air into the side intake that would be a good first step. A water spray system like in the Sti comes to mind too. I don't know if there's room for a bigger intercooler and I get the impression that air flow is the main limiting factor. What mods besides the Gt4 scoops have people seen to get more air to the intercooler or engine compartment and to evacuate hot air?
I love the idea of a mid-engine car with a trunk but this is the problem one runs into.

 

[johan]

Reading this, then it gives meaning that APR har ramped up the fans.
The turbocharged Boxster engines feature newly-developed, compact and efficient
low-temperature charge-air cooling. The charge air heated by the turbocharging
process is cooled by an indirect charge-air cooler (ICAC) positioned above the engine.

DME engine electronics
The indirect charge-air cooler is in turn cooled via an additional low-temperature (LT) 718 Boxster/S
cooling circuit. The heated charge air flows through the indirect charge-air cooler
and gives off its heat to the coolant of the low-temperature circuit. The heat absorbed
in the coolant is then dissipated to the ambient air again via the low-temperature
modules accommodated in the side parts on the left and right. The low-temperature
modules each comprise an air/water heat exchanger (radiator), an electric fan on
the inner side as well as internally mounted ram-air flaps to optimize the air flow.
The arrangement of the low-temperature circuit and low-temperature modules with
electric fan and ram-air flaps located behind the side air intakes can be easily seen
from below. The heated charge air is cooled in the low-temperature modules by
means of an air/water heat exchanger. The indirect charge-air cooler (ICAC) has
a partially integrated low-temperature cooling circuit (LT). In other words, the hightemperature
circuit (high-temperature engine cooling circuit) shares the same coolant
expansion tank with the low-temperature circuit (ICAC), but otherwise operates
independently of the HT circuit.

 

[RotorOver]

I’m no cooling system engineer, but from looking at the system diagrams, it appears the issue seems to be with the high temperature system or a component/sub-component. On another thread someone had mentioned the waste gate on the turbo being the culprit, which is more believable to me. The intercooler is there to lower charge air temps on the power production side of things not primarily for cooling. Has anyone tried dropping a GTS turbo in an S (with a third radiator) to see how that works?

 

[CupraLeon]

Something like this in the frunk 😂

 

[johan]

View attachment 27320
Something like this in the frunk 😂

Problem Solved

 

[EuroKip]

IDEA : How about doing away with the low temperature circuit all together. In its place , fashion a stand alone circuit that comprises the utilization of the 3rd radiator and a dedicated circulation pump . That water would be much lower in temperature by not being associated with 200 plus degrees of the primary system. In turn should pull much more heat from inter cooler

 

[solomel]

IDEA : How about doing away with the low temperature circuit all together. In its place , fashion a stand alone circuit that comprises the utilization of the 3rd radiator and a dedicated circulation pump . That water would be much lower in temperature by not being associated with 200 plus degrees of the primary system. In turn should pull much more heat from inter cooler

Brilliant idea (not joking). At some stage I was thinking similar - just inject one more (even weird) radiator for intercooler circuit when I'll come to this point.

From what I understood from COBB tuning notes for 991.2/718. Car is definitely cut the power (torque) when the air coming from intercooler is overheated. Based on that if intake air reached the 156F system limits torque (airflow, ignition timing, AFR etc... depending on internal algorithms). So keeping intake cooler will have a sense if you notice this particular problem (e.g. via COBB logger). My Stage 1 even in hot weather is far from that for regular fast driving (not track).

When we talk about limp mode it is a turbo protection routine - just disables the turbo hot flow... and it is built-in from my suggestion for any car. How is it triggered - I don't know but seems like one of the heat sensors near turbo (probably westgate...)

But... it doesn't matter if the tuner can raise the protection temperatures and cool down the intake air with 1) more fuel, richer AFR, 2) water / water+methanol or 3) physical cooling. Knowing myself I would choose an easier way when moment comes: water+methanol instead of changing the cooling system (except some proven bolt-ons). It is less invasive, switchable, and giving more bonuses.

 

[purekoryo]

Easiest and effective way would be just do a water/meth injection. However you would need a very large reservoir with small/medium flow nozzles (if you’re going to use it for the track). As a matter of fact, if someone is going to protune their car, may even gain an extra 20-30whp with additional timing due to higher octane and lower EGT as a result of cooler IAT.

I’ve done this on three of my previous cars but didn’t track them.

 

[MG718]

IDEA : How about doing away with the low temperature circuit all together. In its place , fashion a stand alone circuit that comprises the utilization of the 3rd radiator and a dedicated circulation pump . That water would be much lower in temperature by not being associated with 200 plus degrees of the primary system. In turn should pull much more heat from inter cooler

I was actually thinking the same thing. The only thing is, what to do with the airflow coming into the side vents? You could possible replace it with an oil cooler which would reeally solve most of the overheating issue. Suncoast's racecar pretty much solved the turbo soleniod overheating as well. I think its quite an endevour though. Really wouldn't see anyone under going that kind of modification unless it's a track car. i would love to but my 987 is the racecar and the 718 is my daily.

 

[b-grif]

I was actually thinking the same thing. The only thing is, what to do with the airflow coming into the side vents? You could possible replace it with an oil cooler which would reeally solve most of the overheating issue. Suncoast's racecar pretty much solved the turbo soleniod overheating as well. I think its quite an endevour though. Really wouldn't see anyone under going that kind of modification unless it's a track car. i would love to but my 987 is the racecar and the 718 is my daily.

The suncoast car is back to having the same issue again. I hit it in my car last track day. Not fun :-/

 

[GTSTALKER]

I was actually thinking the same thing. The only thing is, what to do with the airflow coming into the side vents? You could possible replace it with an oil cooler which would reeally solve most of the overheating issue. Suncoast's racecar pretty much solved the turbo soleniod overheating as well. I think its quite an endevour though. Really wouldn't see anyone under going that kind of modification unless it's a track car. i would love to but my 987 is the racecar and the 718 is my daily.

suncoast is still having overheating of the solenoid even with all the additional changes to cooling

 

[GTSTALKER]

BMW uses a top mount air water intercoolers design on the s55 engines, similar to the top mount design in the 4 cylinder turbo cars. They have made replacements that are more efficient and have better design and dual pass cooling without having to increase the footprint of the intercoolers itself. I would imagine, it’s just as possible with our cars and would help IAT’s significantly. They also make upgrades heat exchangers similar in nature to better cool the fluid that runs through the air to water intercoolers. Combined, it would significantly reduce IAT’s

pic for reference

 

[b-grif]

suncoast is still having overheating of the solenoid even with all the additional changes to cooling

Anyone know if that upgraded turbo kit will solve that problem? I’m looking at it, and it’s 5 grand for the turbo. Cheaper than changing cars and some other options....

 

[GTSTALKER]

Anyone know if that upgraded turbo kit will solve that problem? I’m looking at it, and it’s 5 grand for the turbo. Cheaper than changing cars and some other options....

Possibly, I guess it depends what actuator they’re using.

 

[purekoryo]

Anyone know if that upgraded turbo kit will solve that problem? I’m looking at it, and it’s 5 grand for the turbo. Cheaper than changing cars and some other options....

Upgraded hybrid turbo will be slightly cooler. But if you run higher boost to actually use it like what it was designed for, it will be hotter than with the oem turbo. Not worth the 5 G to run slightly cooler and additional turbo lag. Typically you upgrade the inter cooler along with larger turbo if you want to take advantage of the reason why you upgraded in the first place.

 

[b-grif]

Upgraded hybrid turbo will be slightly cooler. But if you run higher boost to actually use it like what it was designed for, it will be hotter than with the oem turbo. Not worth the 5 G to run slightly cooler and additional turbo lag. Typically you upgrade the inter cooler along with larger turbo if you want to take advantage of the reason why you upgraded in the first place.

Well currently my car limp modes and I get no power at all, so I’d pay 5 grand to have a car that functions.

 

[purekoryo]

Well currently my car limp modes and I get no power at all, so I’d pay 5 grand to have a car that functions.

How do you know if that’ll resolve the issue? You’re not addressing the root cause. Either way your money. But if it was my money I’d spend it on a decent water meth injection system and a tune to go with it for much much less than 5 G.

 

[b-grif]

How do you know if that’ll resolve the issue? You’re not addressing the root cause. Either way your money. But if it was my money I’d spend it on a decent water meth injection system and a tune to go with it for much much less than 5 G.

I don’t. That’s why I asked.

 

[purekoryo]

BMW uses a top mount air water intercoolers design on the s55 engines, similar to the top mount design in the 4 cylinder turbo cars. They have made replacements that are more efficient and have better design and dual pass cooling without having to increase the footprint of the intercoolers itself. I would imagine, it’s just as possible with our cars and would help IAT’s significantly. They also make upgrades heat exchangers similar in nature to better cool the fluid that runs through the air to water intercoolers. Combined, it would significantly reduce IAT’s

pic for reference View attachment 27465 View attachment 27466

I agree and this would also get you another 15-20 hp with additional tuning.