S3 intercoolers!!

[FULLBORE]

Am i missing something..... why on earth do all these mqb cars uprated intercoolers fit in the SAME PLACE as the oem coolers? Is this some sort of design flaw? Its designed to be cooled by AIR. So why on earth stick it behind a HOT radiator?

There is a REASON ttrs and rs3 intercoolers are ACTUAL front mounts. Im baffled by this. A front mount that recieves air first is always going to be better than one that sits between TWO other radiators.

I cannot bring myself to buy an uprated one designed for the tts because of this.
might aswell jump ahead and buy a ttrs cooler and fit that instead.
infact, i bet a standard ttrs intercooler works as well if not better than these uprated jobbies....

Whats others thoughts on this?

 

[Damo S]

Probably because cooling the engine was considered more important than cooling the intake charge to get a few more bhp. But yes I would agree it's a bit of oversight by whoever designed the layout.

I can say that the uprated intercooler does make a bit of a difference though, especially when on full throttle for a period of time. The power doesn't fade like it does on the stock intercooler, most noticeable in hot weather. Fwiw my car made 305 (I think) bhp with just an uprated intercooler and OEM Intake mod on a day when it was 25C. Not necessarily huge gains but it did feel a bit quicker with no power fade and considering it was a pretty hot day, when turbo cars of old would have felt pretty flat, I thought it was decent power.

Those mods were put in place ready for a remap not just for the gains by themselves. Whether its worth upgrading the IC without a remap I dont know, because they are expensive / not much bang for buck which I believe is partly due to the ECU compensating for the colder intake temps by reducing the boost level a bit. It didnt really go over 1 bar when as far as I know they are supposed to run "up to" 1.2 bar (in 4th gear and above). Unfortunately I dont have any before / after IC install boost level figures for comparison, but I do know that others have reported seeing higher boost levels in the summer compared with winter. Apparently they do this to produce a more consistent power output (depending on intake temps?). All well and good but I think it means the stock map will undo some of the benefit of having a more efficient intercooler.

If you are going to get a remap or live in a hot country then its definitely a worthwhile upgrade, otherwise I wouldn't bother.

 

[Speedychuck]

I didn’t realise the intercooler was day in between the radiator and the air con condenser. Definitely a bit of a design flaw. Normally the air con condenser is first in line. Which is at the front on the s3? Is it definitely engine cooling?

most modern cars, BMW’s at least, have gone over to chargecoolers which are far better imo. Shame Audi didn’t go that route.

 

[Damo S]

BMW’s at least, have gone over to chargecoolers which are far better imo.

Pros and cons. It depends where the charge cooler is located. On the old ST205 GT4 it was sat at the top of the engine so any length of time sat in traffic the unit would be heatsoaked, become ineffective, and take some time driving at reasonable speed to cool the thing down again (much like top mounted intercoolers such as those on the st185 GT4, original imprezza, etc). They are great when cold but lose a bit of edge once they become heatsoaked and never really get very cold again. I guess they suit the style of driving where one would usually poodle along with the occasional blat.
Then there are minor downsides of additional weight and complexity having a pump, pump / level sensors, the liquid filled charge cooler and it needs a front mounted rad still anyway.
On the plus side it typically means a shorter and more direct route from turbo to intake manifold rather than having to go to the front of the car and back, meaning a path of lesser resistance as well as a bit of reduced turbo lag.

On my old ST205 Gt4 the charge cooler was removed and replaced with an uprated Supra front mounted intercooler, which performed way better. The thing was pretty huge though so not really a surprise, but it added a bit of turbo lag.

 

[Marky-s3]

Am i missing something..... why on earth do all these mqb cars uprated intercoolers fit in the SAME PLACE as the oem coolers? Is this some sort of design flaw? Its designed to be cooled by AIR. So why on earth stick it behind a HOT radiator?

There is a REASON ttrs and rs3 intercoolers are ACTUAL front mounts. Im baffled by this. A front mount that recieves air first is always going to be better than one that sits between TWO other radiators.

I cannot bring myself to buy an uprated one designed for the tts because of this.
might aswell jump ahead and buy a ttrs cooler and fit that instead.
infact, i bet a standard ttrs intercooler works as well if not better than these uprated jobbies....

Whats others thoughts on this?

Get an intercooler n stop moaning lol if your that bothered do away with the air con rad, intercooler makes huge difference when tuned

 

[Speedychuck]

Pros and cons. It depends where the charge cooler is located. On the old ST205 GT4 it was sat at the top of the engine so any length of time sat in traffic the unit would be heatsoaked, become ineffective, and take some time driving at reasonable speed to cool the thing down again (much like top mounted intercoolers such as those on the st185 GT4, original imprezza, etc). They are great when cold but lose a bit of edge once they become heatsoaked and never really get very cold again. I guess they suit the style of driving where one would usually poodle along with the occasional blat.
Then there are minor downsides of additional weight and complexity having a pump, pump / level sensors, the liquid filled charge cooler and it needs a front mounted rad still anyway.
On the plus side it typically means a shorter and more direct route from turbo to intake manifold rather than having to go to the front of the car and back, meaning a path of lesser resistance as well as a bit of reduced turbo lag.

On my old ST205 Gt4 the charge cooler was removed and replaced with an uprated Supra front mounted intercooler, which performed way better. The thing was pretty huge though so not really a surprise, but it added a bit of turbo lag.

I take your point, but you would hope that technology has helped things improve somewhat since the 90’s. Was the cooling radiator for the chargecooler fan cooled (effectively) on the st205 for example? The st205 wasn’t the kind of car that would monitor intake temps and limit boost to reduce set etc.... I’m sure a supra ic will have improved things though, I’m not saying intercoolers are bad.

I also suffered the woes of heat soak in the 90s. I had a pulsar gtir running about 300bhp. You just be from the same era as me. If I gave it any after being in traffic, it would detect knock and put the car into limp mode!!!! Had to turn it off and on again to resolve.

Im talking about cars like the m4, and the m140i. Both of these have factory chargecoolers which are effective and good enough not to need upgrades on power increases and make for very short boost piping. My 135i had a crappy intercooler that I had to upgrade as step number 1 because there was no headroom at all. I saw the chargecooler as an improvement hence the post. Always good to discuss these things though, I hadn’t considered heat soak as a factor on the m4 so would be interested to see if it does have similar issues to your celica.

 

[Damo S]

Yep same era. The st205 had the typical sprung actuator controlling the waste gate, and then an ecu controlled device allowing it to boost higher (it ran 9 psi in 1st which was the real actuator pressure, then 14psi in all remaining gears by activating what was effectively a bleed valve). It had a map sensor and intake temp sensor for controlling the fuel but when things got out of hand all it ever did was pull the timing but it didnt reduce boost levels as I recall. There was no fan on the cooling radiator.

The previous model had a top mounted intercooler and that was awful. A common mod was to mount a slimline 12V fan on top to blow away any heat, and that worked to an extent but made the car sound like a hoover when sat in traffic.

I wonder what extra tech they have included in modern charge coolers. They are definitely better at controlling sudden spikes in intake temps provided they are not heatsoaked.

 

[FULLBORE]

Get an intercooler n stop moaning lol if your that bothered do away with the air con rad, intercooler makes huge difference when tuned

Im not moaning. Im simply stating the obvious. I mean, everyone seems to run out and buy these UPRATED intercoolers which are wedged back in the same hot spot as the old one lmao.

Makes no sense. I mean, did no one ever wonder why even AUDI mounted a proper front mount intercooler on their highest performing model ( rs3/ttrs). Clearly a reason for that.

Look at them baun performance fmic. They are just crappy ebay intercoolers but are mounted on the front. With consistent piping to the turbo and inlet. Yet that cheapo style cooler out performs most uprated ones.....

Why is that?

Because its not being heat soaked by the radiator sandwich.

 

[Damo S]

You are right its not an ideal spot but install is relatively easy and it does make a difference especially when the car is remapped. I'm not sure how easy it would be putting it somewhere else.

 

[Salik Sajid]

If u dont like the stock location uprated intercooler then theres uprated fmic available for mk7 Golf GTI or R, do check forged or cts. I think it would need some trimming to fit inside S3 bumper.

 

[Speedychuck]

Yep same era. The st205 had the typical sprung actuator controlling the waste gate, and then an ecu controlled device allowing it to boost higher (it ran 9 psi in 1st which was the real actuator pressure, then 14psi in all remaining gears by activating what was effectively a bleed valve). It had a map sensor and intake temp sensor for controlling the fuel but when things got out of hand all it ever did was pull the timing but it didnt reduce boost levels as I recall. There was no fan on the cooling radiator.

The previous model had a top mounted intercooler and that was awful. A common mod was to mount a slimline 12V fan on top to blow away any heat, and that worked to an extent but made the car sound like a hoover when sat in traffic.

I wonder what extra tech they have included in modern charge coolers. They are definitely better at controlling sudden spikes in intake temps provided they are not heatsoaked.

the pulsar I had, had a similar system. Typical for the era really. I replaced it with electronic boost control which gave me full control from the driving seat. I miss the simplicity of this kind of tuning... using an safc to modify maf sensor signals etc.

I’d also be interested to know just how good modern chargecoolers are, but if bmw have moved over in favour of air/air coolers then I’d imagine there must be a benefit!

 

[MikeParkin]

Wagner is the best.

 

[Damo S]

the pulsar I had, had a similar system. Typical for the era really. I replaced it with electronic boost control which gave me full control from the driving seat. I miss the simplicity of this kind of tuning... using an safc to modify maf sensor signals etc.

I’d also be interested to know just how good modern chargecoolers are, but if bmw have moved over in favour of air/air coolers then I’d imagine there must be a benefit!

They are and always were better at controlling temp spikes, so from that perspective they are better. The problem is then shifted to keeping the charge liquid cool over time and the effect that can have on performance. Like you say, one would think BMW have put a fair amount of effort into it.

 

[Rick @ Unicorn Motor Dev.]

Charge cooling is not done for increased cooling, it is to shorten the path between turbo and intake manifold.

Also TTRS/RS3 have much worse performing intercoolers from the factory than the S3.

A wagner intercooler on an S3 offers significant benefits. around 30C less intake temp on an average dyno pull as a comparison. It also has less pressure drop across the core which effectively means free boost.

Rick

 

[w.h.i.p.p.e.t]

The Wagner seems to be regarded as the best for the 8V, at least on the things I've read it does.

But, does it fit without any modification? I've read that there is some 'work' required, but I think that has to do with removing the AC radiator?

 

[Damo S]

Increased cooling may not be the primary reason but that is something they can provide. Since core metal in contact with water will dissipate heat about 4 times more quickly than in contact with air, they can (in theory) provide better cooling as well as better control of sudden charge temp rises. Charge coolers are also still effective at zero or low speeds since (for a short period of time at least) they are not immediately dependent on airflow, where as an air / air interooler becomes more and more effective with speed but basically doesn't work at all at zero speed.

This is assuming that the air / cooler liquid temps are similar. Once that liquid gets hot in the charge cooler it becomes ineffective at any speed until its temp has been bought down again by whatever means (rather like top mount air to air intercoolers once they are heat soaked). The cooler liquid temp management will make or break a charge cooler system so it would be interesting to know what BMW have done in that respect.

 

[Rick @ Unicorn Motor Dev.]

BMW will not start pumping coolant through the charge cooler until the car is under load.

 

[w.h.i.p.p.e.t]

...But, does it fit without any modification? I've read that there is some 'work' required, but I think that has to do with removing the AC radiator?

Anyone got any feedback after fitting one?

 

[w.h.i.p.p.e.t]

 

[Damo S]

Dont know for sure, but one of the reasons I went for the revo one since it didnt need any butchering. I'm lead to believe the wagner one is a better core but the revo one does the job nicely

 

[w.h.i.p.p.e.t]

Dont know for sure, but one of the reasons I went for the revo one since it didnt need any butchering. I'm lead to believe the wagner one is a better core but the revo one does the job nicely

I wonder how much of a difference there is between them all. I'd prefer not to have to cut anything to make it fit if there's not much difference. Seem to remember reading a good comparison test on here somewhere. Will have to go search for it.

 

[Damo S]

I suspect you wouldn't really notice any difference between them on the road. But you would between one of them and stock especially if you have had a remap, and even more so, in warmer weather.

 

[Marky-s3]

Spool is great with wagner and on hybrids it shows it flows better with earlier spool over others and tbh most company's that fit them know where to cut mine was done on a facelift 2 years ago with 0 issues

 

[Damo S]

Spool is great with wagner and on hybrids it shows it flows better with earlier spool over others and tbh most company's that fit them know where to cut mine was done on a facelift 2 years ago with 0 issues

There is no obvious difference in spool up time between mine (revo) and the stock one

 

[w.h.i.p.p.e.t]

Spool is great with wagner and on hybrids it shows it flows better with earlier spool over others and tbh most company's that fit them know where to cut mine was done on a facelift 2 years ago with 0 issues

Thanks. I want to fit it myself when I get one. So wondered if there was some guidance etc.

There is no obvious difference in spool up time between mine (revo) and the stock one

I quite like that Revo do the matching pipework, whilst you're in there may as well They also have detailed fitting instructions.

 

[Damo S]

I quite like that Revo do the matching pipework, whilst you're in there may as well They also have detailed fitting instructions.

Yep had all that fitted with mine (not myself though)

 

[Check5]

The chart below is a comparison of airflow data that have measured. The intercoolers were tested using a flow bench set to a depression of 28″ of H2O.