So, first of all, I want to make some introductory notes which, while being obvious for some, might be of great value to others, who aren’t so technically inclined, or just simply haven’t had it explained this way.

The Mini Cooper S R53, because of the way the intercooler sits on top of an already very tight and supercharged engine, once tuned, starts struggling with heat. While the coolant temperature is easy to address, installing a lower temperature thermostat, for instance, the Intake Air Temperature (from now on referred to as IAT) not so much.

The Mini Cooper S R53 is not like the Mini Cooper S R56, in which you can “easily” get 70 ft-lb from a tune.
The easiest way to notice a bump in performance on a Mini Cooper S is to install a reduction pulley on the supercharger (which is about the only mechanical way, along with the enlarged crank pulley, that you have to add more boost) and increase the rev limiter.
But each of these mods will, in turn, demand more from the supercharger and take it beyond its optimal working range. Why? Because it will spin the supercharger faster, thus generating more heat.

For you to have an idea, with the stock pulley and rev limit, at 6950 RPM, the supercharger is spinning at 14749 RPM. With a 17% reduction pulley installed, the supercharger will be spinning at 14749 RPMs at 5761 RPM, so, almost 1200 RPM down the rev range. At 7500 RPM, with the 17% reduction pulley, the supercharger will be spinning at 19200 RPM, which is 30% more than with the stock pulley at the stock rev limit (6950 RPM). We all know that manufacturers build stuff with tolerances, but 30% will always be 30%, and the supercharger’s flow chart/efficiency map are not merely indicative.

The stock IC copes well with the original stock pulley and rev limiter, but it just can’t cope with a reduction pulley and higher rev limits, because it starts dealing not only with its own inefficiency, but with the supercharger’s as well.

And why is this added heat so prejudicial? Well, not all air is equal... when you crank up the boost you will be generating more air, but because of the way the air is compressed, the air will present less density, thus the need to cool it down to increase density. Think of density as the air’s quality.
That’s why in a colder day/night, the car responds better than in a warmer day/night... the air density is better.

So, now that we understand that with more heat comes more responsibility, it’s time to address the variable we can address... the intercooler!

We have different intercooler systems (Top-mount; Chargecooler; and Front-Mount) available to our Mini Cooper S R53, each with their advantages and disadvantages.

I don’t want to go to great lengths exploring all the different solutions between the 3 types of available systems, so I’ll focus on the more generic ones and sum it up like this:

Top-mount:

Advantages: Easy installation; Maintenance free; Plug and Play
Disadvantages: Worse in keeping intake temperatures down

Front-mount:

Advantages: Good at keeping intake temperatures down
Disadvantages: Loss of boost due to piping re-routing. Not plug and play; many require A/C removal.

Chargecooler:

Advantages: Good at keeping intake temperatures down
Disadvantages: Not plug and play; Adds the weight of the water from the circuit; the electric water pump; external reservoir and the radiator; May lose a little bit of boost when compared to some top-mounts.

I decided to do this review because I was going crazy with the fact that there was no data available on the Pro-Alloy Top-Mount intercooler, which had a unique design and, from my understanding, all it needed to perform quite well. Thing is, not only we had no data, as there was some kind of criticism in the air regarding fitting, but without being very objective about it... how it fails, why it fails, etc...
So, I came to the conclusion that, in this particular case, if I wanted data, I would have to collect it myself. And if I wanted to know exactly what was going on with the fitting, I’d be better speaking directly to the source. And this was when I decided to get in touch with Pro-Alloy. So, I sent them an e-mail, providing some background on myself, the questions I had and what I had to propose: A discount in return of a complete review of their intercooler. And, although my main objective had always been the Pro-Alloy, I also sent a similar e-mail to another company, proposing the exact same thing, while letting them both know of this fact.

The other company’s reply made me laugh, as I had been quite thorough in my explanation, and they simply pointed me to a site where I could see the result of their IC on a dyno, it was like: Dude, this is all you will ever need to know about our IC. I didn’t even bother replying.

And then, when I was starting to lose hope, Pro-Alloy answered...

Regarding the fitment issues they had, this is what Chris Hazell wrote me:

So, contrary to the other company, they did take the time to read my whole e-mail, found it to be a very interesting approach, and treated me with due respect (things that I do value). So, after discussing all the details, and making sure we were on the same page, we were good to go. Oh, one aspect I must highlight is that I told him I would compare their IC to as many others as I could, but that in no way I would alter the data in their favor. So, whatever their IC would show, would be exactly what I’d be showing in the review. And to this, he also replied with no hesitation, telling me that that was precisely what they were after, showing the utmost confidence in their product, which, in turn, gave me the confidence to keep their product.

Almost all of the tests (only the Airtec wasn’t) were made in my private road, in the exact same places. The aim of the tests was to try and replicate real life situations with which one can easily relate to and even compare, if curiosity arises... so, the tests consisted in:

A 3rd gear pull in a straight line, from 2600 to 7200 RPM
A 4th gear pull in a straight line, from 3150 to 7250 RPM
A 3rd to 5th gear pull (from 2600 in 3rd gear until 6500 RMP in 5th gear) in a straight line, with a 30 second rest period, and a new pull, 2nd and 3rd gear, but now uphill

All these logs were at WOT (Wide Open Throttle).

Almost all of the logs (again, with the exception of the Airtec) were captured via my ByteTronik data logger, which captures data with 150ms intervals.

What I couldn’t control: The weather.

Relevant notes:

The ICs I tested directly on my car were: Chargecooler (my previous setup); stock; and Pro-Alloy. I feel it’s important to highlight this as these are the more “apples to apples” comparison, although I do feel there is room for some extrapolations, based on the data collected from the other cars. But we’ll get there...

My car has: A Sprintex supercharger with a 60mm pulley, a TPR-1 Cylinder head; a Newman cam (the first ones); Mynes V2 headers with tomcat and JCW catback; ByteTronik tune;

The car with the GRS Motorsport IC has: Eaton M45 with a 17% reduction pulley; 1320 Catcam; TPR-2R Cylinder head; Janspeed de-cat headers with JCW catback; custom tune.

The car with the Airtec IC has: Eaton M45 with an 18% reduction pulley; Worked cylinder head; Newman cam (ph2); Milltek de-cat headers; Milltek catback; custom tune.

One of the cars with the GP IC has: Eaton TVS900 with 60mm pulley; Worked cylinder head; Newman cam (the first ones); OBX headers with tomcat; Direnza catback; custom tune.

The other car with the GP IC (from which I only have data for the 3rd gear pull) had: Sprintex supercharger with 64mm pulley, TPR-2R cylinder head; 1320 Catcam; Mynes V2 headers with de-cat; JCW catback; ByteTronik tune.

I focused on boost, IATs and, when possible (only on my car which has the Bytetronik software installed), on Air mass as well.

So, enough chatter for now, let’s get down to the numbers and charts...

3rd gear pull, IATs



3rd gear pull, Boost



3rd gear pull summary



3rd gear pull summary in numbers



4th gear pull, IATs



4th gear pull, Boost



4th gear pull summary



4th gear pull summary in numbers



3rd gear to 5th gear pull, IATs



3rd gear to 5th gear pull, Boost



3rd gear to 5th gear pull summary



3rd gear to 5th gear pull summary in numbers



30 second recovery



30 second recovery in numbers



2nd and 3rd gear pull uphill after rest period



2nd and 3rd gear pull uphill after rest period in numbers



My considerations and analysis:

An IC, just as another component of the car you choose to change, should be well thought, so you know it will work its best in your given application.
I can’t determine if a certain IC will be the best for your particular application, but I think I can give you a rough guide, based on my example. With the chargecooler, I had best IATs than with the Pro-Alloy, but I was also seeing roughly less 1.5-2 psi than I am seeing now with the Pro-Alloy. If I had a conservative pulley on the Sprintex, I could try and put an even smaller pulley on it and keep the chargecooler, but that’s not the case, as it’s already near its limit (reduction pulley wise). So, in order for me to win back some boost, once a smaller pulley wasn’t an option, I had to look elsewhere, hence I tried going with a different IC. Once I put the stock IC on in another situation, the boost came up, but the IATs were just too high, so I knew that would not be a valid option for me. With the Pro-Alloy, my honest expectations were to pick-up some boost (compared to the chargecooler setup), and that my IATs wouldn’t fall in the danger zone. And WOW, I was really surprised in the way the Pro-Alloy performed. It was a massive difference in average boost, and hell, I only lost 0.2 peak psi (in the lower gears) when compared to the stock IC! In the higher gears, I think the Pro-Alloy will see even more boost than the stock. And fortunately, not only the Pro-Alloy excels in terms of boost, but it also performs wonderfully in terms of keeping those IATs down!

So, how does it compare to the others (GP; Airtec; stock; GRS and chargecooler)?

Let’s see...

The Airtec data is the only one I couldn’t capture with my ByteTronik data logger, or do the tests in the same place, as my friend lives 200 miles away (my own private road can only stretch so far ) His data was captured by other logging software, which is not as fast as the ByteTronik, so, not ideal, but it is what it is. For a fact, I might also add that my friend has now changed the Airtec for a GP IC and picked-up around 2 psi of boost, subsequently, seeing higher IATs as well.

The Airtec seems good at controlling IATs but at the expense of losing you boost, so, as boost and IATs rise proportionally, it’s not directly comparable, i.e. it holds IATs better because it’s doing less boost, which leads me to believe that, probably, at similar boost levels, it wouldn’t cope as well as we are led to believe at a first glance when looking at the numbers. I know this is just speculation, but I don’t think I’m that far off, to be honest, at least, considering what I saw in my car with the three different setups (Chargecooler, stock and Pro-Alloy).

The stock IC: Not much to say, really... basically, it’s great for boost alone, but it just can’t keep the IATs down.

The chargecooler: Great at keeping IATs down, but it robs you boost, so, if you’re already at the limit of your pulley choice and don’t live in a very demanding climate/terrain, maybe you could do better with a Pro-Alloy TMIC.

The GP IC: It’s also good for boost, but from what I could see, it can’t match the Pro-Alloy in terms of keeping the IATs down. If you look closely to the data, you will notice that there is only another car which is close in peak boost to mine with the Pro-Alloy, which is the car with the TVS900 and 60mm pulley. But, even that one, sees considerably less average boost than I do, so, mine, despite having more average boost in all the pulls, was able to keep lower IATs than the GP. We could argue it could be due to the Sprintex being more efficient than the TVS, but if you take a look at the “3rd gear pull summary in numbers” you will see that the other car that also has a GP IC, has a Sprintex with a 64mm pulley, thus seeing considerably less average boost than mine (15.17 psi vs. 16.37 on the Pro-Alloy), and yet, IATs rise 3 Celsius degrees more (21 Celsius degrees rise vs. 18 degrees rise on the Pro-Alloy).

The GRS Motorsport version: As some of you might have noticed by the odd boost curves, my buddy had a problem in his car (and this is also one of the reasons why data logging is so important), we suspect that it was his tensioner that must have been very near the end of its life, as his belt snapped the week after we logged his car.
But even though the boost loss he was seeing, which actually ends up being favorable to an IC on the account of what I’ve explained earlier (higher boost will see higher IATs), the GRS didn’t excel in any particular category. For the record, from older logs, his car was seeing around 15.6 psi of maximum boost. So, if the car wasn’t losing boost on the day we’ve logged it, the IATs would have been higher, for sure. He says it’s not uncommon to see 60-70 degrees Celsius when at WOT. My friend who bought me my Chargecooler, previously had a GRS Motorsport, and he also told me it was pretty common to reach those high temperatures... and this, with a still conservative 15% reduction pulley. He lives in a very demanding terrain, but now, with the chargecooler, I think the maximum he saw was 42 degrees Celsius. He is now thinking of going to a 17% pulley, as IATs wise, he has margin for it

A little note on the Air mass data, which I find really interesting, as it gives you an idea on how your boost is being “eaten” by the engine... the more the better.
You will see that the Chargecooler has the best ratio of produced Air mass vs. Boost, meaning that despite robbing you a little bit of boost, it is indeed very efficient at what it does, hell, in some cases, it almost manages to reach the stock IC Air mass values, with circa less 1 psi in average boost. But the Pro-Alloy is king in this value as well.

Regarding one thing people often talk about, which is the recovery rate, I did try and replicate it with the 30 second rest period. Yes, the GP and the Stock ones excel at this, but they do get hotter than the other contenders, so, yeah, they do recover faster, but I’m really convinced that is mainly due to having more heat to recover from, at the first place. If you take a look at how fast the IATs rise, after pulling a 2nd and 3rd gear uphill once the rest period is over, in both cases, I think you will corroborate just that.

Hope you guys have understood and enjoyed this review, and that this information can actually shed some light on the Pro-Alloy, as well as in some of the more popular solutions available out there.

I want to thank Pro-Alloy, in the person of Chris Hazell, for sincerely trusting and valuing my work. I also want to thank all my friends that came to meet me in my own private road, as without them, it would not have been possible to conduct all the testing, data compilation and analysis, that, hopefully, will help the MINI community.

 

You did a great job with this as far as data collection and display but the widely varying vehicle set makes this pretty inconclusive unfortunately.

May I ask why you didn't just swap all the intercoolers on to one car?

My suspicions are that the numbers would be a lot closer from intercooler to intercooler if you did.

 

A labor of love for sure but yes, I would like to see the comparison based upon a single vehicle with the only the intercoolers being different.

 

Thanks, guys.

As you can see, I'm not a very active member on this forum, nevertheless, I found that providing the forum this information would be of value.

I don't want to sound arrogant, but if you already knew me from Mini Torque, maybe you wouldn't have made such observations, because my background speaks for itself.

I will make a quote of what I wrote when answering to a similar observation, so I don't have to repeat myself.

Furthermore, I'd like to add that I never estimate/extrapolate stuff that hasn't been very well thought first.

So, when I read the last part you wrote, I could't help to be a little disappointed, because you're not only questioning my findings, as you are questioning all my work, because, let's face it, if they're all so close, I shouldn't have bothered to do the tests in the first place, right?
The explanation is pretty thorough in the initial post, but after what you wrote, I can't help to ask you some questions...
You say that if all the intercoolers were tested in the same car, the results between them would have been pretty closer. Would they? Are you sure?
Well, I've tested 3 intercoolers in the same car, MY CAR, the one I drive for 11 years and in which I've tested a lot of different stuff throughout the years... And guess what, the results are VERY different between them, and I can't understand how you fail to see that. This leaves me with one of two possible conclusions: You haven't read and looked at what I did with the proper attention; You can't process all the data how it should be processed because you lack the knowledge.
Either one is definitely no excuse to go and criticize other people's work, well, in fact, what it should is precisely prevent you from doing so.

But I now urge you to delve a little deeper into this.

In the same car, from changing intercoolers, in the same run, you had a peak boost difference of 1.8 psi. And, from my understanding, you consider this to be a negligible difference. Let’s not forget, we’re talking of a 1.6 supercharged engine, not a 2.0 turbo one
What if I told you that, in some cases, you might not see such a peak difference in boost, when changing from a 15% to a 17% reduction pulley?

And, in the same car, from changing intercoolers, you saw, in the same run, a 22.5 Celsius degrees difference in IATs delta. Well, if this doesn’t quite cut it, what would make it a significant difference to you, then?

But please, do feel free to make your own testing. If that testing proves that my assessments are wrong and yours are right, I’ll be the first to publicly admit I was wrong, and congratulate you on your finest work.

 

citro - thanks for the write up. It seems to me to be very comprehensive. I would say to the other posters that want the different IC's in the same car, had you done that, someone, perhaps not the other posters, but someone would have brought up that the time it took you to change the IC's in the same care the weather and engine temps would have changed the data.


So to you citro - thank you for all the hard work you and your friends have done. The data here is valuable and I for one appreciate it.

 

THANK YOU!



A most excellent post.

Thank you for taking the time to compile some hard data, it is quite interesting and makes for comprehensive reading.

Very well done.

Please stick around and keep on posting up the good stuff.

Cheers!

 

 

The best knowledge does not come cheap and if you want just 2 b spooned to the mouth, good luck for U. Just a bit of due diligence (what is that in the era of FartBook?). Do some internet detective work and U will be well rewarded. Knowledge cannot be dumbed down for the masses, and that is one of many reasons U don't see citro posting here.

Quik answers are typically crap, at least in my books that I seldom read.

 

All the above work and charts are cool, but the data is greatly flawed.
Coming out of the last twenty plus years of testing in the Aerospace world, I'd be laughed at and probably demoted if I turned in this work.

And both because of my Aerospace background, and my cylinder head and manifold porting work (what works on a flow bench and what doesn't) for the last 30+ years, "flat" surfaces...are NOT, conducive to smooth, good air flow. ANYONE ever seen an airplane wing with a FLAT leading edge..? It's the SAME thing...smooth airflow required..!

The flat surfaces on all (that I've seen so far) between the tubes are a joke. Yes, the GRS has a round surface, slightly better than flat. An ellipse or a triangular shape would be much better.
Notice the air flow directors, diverters, straighteners, whatever you want to call them, that are in the two OEM inter coolers (inlet side). THIS...is what they ALL should look like.

As much as I'd like a little larger cooler (without the GP price) for SoCal summers, I guess the OEM cooler is what will stay on my car.

Mike

 

All things being equal, without measuring actual HP/TQ on the dyno how do you know you lost power or gained just by boost numbers? (Not arguing just a friendly convo)

I know this review was more based on intercooler IAT but OPs concern seemed to be he didn't want to lose boost.

Boost is just a measurement of restriction in the end, if aftermarket intercoolers lowered peak boost but it loses no power you've achieved something. Less boost means less heat so less chance of knock isn't it?

Unless the boost you're losing is due to a leak which is a bad thing.

Just that in my other car (07 Mustang GT) with a blower, some mods like long tube headers made me lose peak psi which in turned helped sustain lower IAT bit longer but the car felt more powerful. Not my car but other Mustangs done in similar manners have gained HP/TQ on dynos whilst lowring boost with other mechanical mods like bigger intake, headers etc.

So without dyno numbers don't think you can solely base it on IAT and Boost to see how well an intercooler performs. If you are solely basing it on effeciency then yes.

 

My opinion fwiw is keep the stock intercooler get a aqua mist kit nothing is better for cooling than that.

 

Exactly this. Seems to be a common misconception around here, and not just in this thread. :thumbup:

 

And of course the stock unit will always have the fastest recovery from heat soak. It's the thinnest of them all.

 

Recovery isn't as important as stability with IAT's for tuning and performance consistency.

 

So profound that I have a hard time comprehending.

You don't control the stability of IAT. IAT in a forced induction is the function of engine RPM -> compressor RPM -> compressed air temperature, which is not a linear relationship. Ideally the intercooler will give you a delta T temperature but again there are many factors that determine this delta T, which includes the speed of the car and the heat transfer from sources such as the radiator and if the thermostat is open or closed.

In short you have next to no control with the stability of IAT with TMIC in the R53. Your best hope is to implement as efficient a IC that has the best heat exchanging capacity and with the least restricted induction air flow. Sound so simple but not because we are dealing universal gas law and fluid dynamics.

 

Yep, well said.
In my modest searching of intercoolers for the R53 cars, stock or the slightly larger GP cooler are the "radiators" to have. I personally would not spend money on my car on parts that do little to nothing...
If you want better cooling, put in a coupla (3 or 4) small tubes to mist water or alcohol mix over the OEM intercooler. Nothing new, the WWII turbo charged fighters did this way back then. Still a VERY viable solution, and cheaper than a lesser aftermarket cooler.

Mike

 

Can’t control IATs, huh? Interesting. So nobody here has ever heard of an AWIC and their increase in popularity specifically due to their ability to stabilize IATs?

Very interesting indeed. The very inclusion of any intercooler, as well as differences in design methodology, is testament to the ability to control IATs. If they produced zero effect, as the words you’ve used are implying, they would never have been included. The intake elbow would be on the other side, and it would be a direct air intake. But alas, nope, we have a TMIC that controls IATs. It heat-soaks rapidly, sure, but again, for the sake of tuning, stable IATs are more important than “hero run” chilling.

 

So, Mike, I was searching for some information regarding this review and decided to chime in, after seeing your observation.



How can you say my data is flawed if data was presented "as is" and carefully explained in my initial post?

Do you have any idea how much time and effort was required to put all this together?



I don't work for NASA, nor does this review intend to be the "ultimate guide for intercoolers"... this review is to provide data on different intercoolers in a specific set of conditions, period.



And after having written that my data was flawed, you end up saying "I guess the OEM cooler is what will stay on my car". So, what should I reply to this? I guess only a "good for you" makes sense






o2sys, you are correct on your analysis, but don't forget that the 3 intercoolers tested on my car were tested in the same conditions, no other parts were changed. So, you know that the intercooler is the only part contributing to the boost change. And as you should also know, the R53 aren't properly easy cars to dyno, so the differences between ICs on a dyno, for me, have little value, sorry. I should add that I know my car pretty well, as well as the stretch of road where the ICs were tested. For what it's worth, I own my car for 13 years and it's my daily, so, trust me, I do pick up the little differences with some ease, as I believe anyone in the same situation would. But as I didn't want to get into a subjectivity/possible placebo discussion, I kept it to the numbers.




Thanks, pnwR53S. Truth is, time doesn't stretch and we can't be everywhere we would like to be, so we end up choosing to stay in the places where our presence is most appreciated, hell, this is (or should be) inherent to human condition. So, yes, for a person like me, it does hurt when I see some type of comments as I did. And the reason I decided to put this thread in MINI forums that I don’t attend so frequently, was precisely because I thought the information in it should be shared with the most MINI owners possible.

Take care, folks.

 

Anyone have a picture of the inlet side of the pro alloy? Wondering if the core is tapered like oem

 

tons of photos if you do an image search. they seems to have changed the outlet design now. or you can make your own GP if you have a TIG welder and skills like Nik Blackhurst using two standard issued R53 IC.

 

I need to get myself a TIG. I have a grinder and I can use it very well. I suck at welding though as I get too tense.

While I am shopping I might as well pick up a plasma cutter too.

 

I have searched for photos and not found any, they all deceptively hide what the core looks like.

The only one I found photos of is the GRS motorsports version, that is what I am leaning towards, the core has air diverters like the OEM core

 

The other detail too is the OE cross tubes have nice funnel shape flares and I have not seen any aftermarket one has. I certain can see why as building them this way will cost a lot more in tooling. I would like to scrutinize the aftermarket ones against the OE side by side on all the overlooked details.

 

Found a photo of the WIP GRS TMIC that you can see the cross tubes. It is on their Imgrum page.




Also this post has more photos of the inlet and outlet.

 

the grs motorsports version has a better design