Further reducing the IAT's will indeed provide a "denser" charge of air and a cooler combustion cycle....which is more healthy for the engine...creates an environment for more power to be made etc. Its only if the cooler denser charge of the compressed air is restricted by inadequate flow through the turbulators to the cylinders (so to fill them fast enough) that flow would become an issue. I have no evidence in front of me to date that suggests the existing flow of the "lesser flowing" .2tt coolers is an issue for this particular engines cylinder requirements.

The chart provided by CMS showing flow between the different model coolers is interesting for one to see however, it does not answer, satisfy nor confirm whether flow is/or causing an issue for the newer .2tt cooler in being able to satisfy or cope with boost levels beyond the GT2RS's high boost levels. Additionally one must also consider that P would have a safety factor built in to the .2tt coolers functionality. I'm sure the .2tt cooler isn't at the end of its rope while operating at full rpm and full boost as there is no evidence provided to date to suggest this is the case. In fact this ".2tt cooler " has been clearly shown in Skands data to provide a significantly cooler (IAT) charge than its predecessor .1 tt cooler (and, at no cost to performance anywhere) in addition to showing these .2tt coolers also out performed certain "un named" and rather expensive aftermarket coolers, that "claimed better performance" which did not live up to those claims. So, just using Skands tests as a text book example, it has proven bigger, attractive looking, higher flowing coolers did basically SFA other than to lighten ones wallet significantly.

So the only thing really missing at this stage is the most important chart and, that is the chart showing the comparitive IAT's? Now if the new and/or old version of CMS's IC's show a cooler IAT than oem .2tt cooler then that may be worth some extra dollars. 2500 extra dollars....i dont know?....yet.

 

bar & plate -new CMS on left, Bell on right (props to CMS for showing their core, many won't...)

 

This is night and day difference.....props to CMS!

 

Guys I didnt interpret anyone as disputing that CMS's coolers (new or old versions) werent of a high quality manufacture or, that CMS were not being sufficiently transparent in their presentations. So yes, props to them and thanks for that. And I would agree the two cores are markedly different in structure but to say one actually works better than the other really requires proof by way of tangible data. The same applys to not only the cores but the finished intercooler products. I would always expect the OEM 's best offering (in this case being the new .2tt cooler) to be the minimum benchmark to base any claims of improvements upon though..

Edit: Its important to remember here that at this stage, and quote me if im wrong here, but it has yet to be proven that the .2tt IC has a flow issue for the engine, even running at the higher GT2RS boost levels. So in the instance of comparing core structures and being able to provide better flow and cooling under the application on the engine type they are being used on, if those benefits are not able to shown on the actual engine during performance testing and data collection then its all becomes rather insignificant and meaningless. One becomes no better than the other so to speak. We all know that the prime objective for any cooler is to acheive a cooler IAT without impeding or reducing the existing flow rate. To have a faster flowing cooler without achieving the lower IAT is in opinion not worth anything unless it can be firstly proven that flow was an issue for the engine to begin with.

Finally I forgot to mention that the .2 engine is 3.8 litres so it also has a larger cylinder capacity requiring a bit more air than its predecessor 3.6. So one would expect that if flow was an issue already for the 3.6 engine then why make a cooler that flows less again?

 

Totally agree! Thanks for posting the pics!

I also think Paul makes some salient points. The 3.8L will flow more so for upgraded vtgs the .2s do seem very reasonable. I don't think Skand did a performance (speed) test with the .2 ICs so the jury may still be out on that one.

 

Skands last posts indicated his times were the same using his new .2tt ic's as the .1tt coolers but he was able to pull consistant fast times due to the lower IAT's whereas with the .1s he was not. I also understood his APR tune had limitatons from extracting any more performance from having the cooler IAT's as well....but his times were definately not less and he said the car felt better than before. Maybe he can chime in and give his own words? But his APR tune is running a lot of boost as well dont forget so, there cant be any flow issues, plus his is 3.6 engine....not 3.8.

 

Can anyone confirm that the GT2RS intercoolers are exactly the same as the regular .2's? We haven't seen the car yet so I'm just not sure. I'd be surprised if P is running 1.6 bar through those.

 

Look on the "PET", the refs for GT2RS ics are the same 997.2's.
When I ordered mine, I didn't ask for 997.2s, but for GT2RSs, and after we realise they were the same.

For the question about the 997.2TT boost pressure, I asked a friend of mine who owns one, his gauge on the dashboard shows 1.0Bar; and my mechanics checked a bone stock 997.2TTS on dyno at 545hp and 1.2Bar???
He checked a GT2RS too, 1,6Bar at over boost and a little less after 5000rpm.

After seeing earls pics of your 2010 core near Bell's, yes, it is night and day!
I noticed the 997.1 core looks like Bell, and 997.2 like yours.

 

.2 ICs are tube & fin (like .1), whereas CMS is bar & plate. My understanding is tube&fin are less expensive to manufacture and used on most OEM applications.

 

Touching on the issue of Skands performance again, it is worth considering that if he was able to utilise/optimize the benefits of the cooler charge from the lower IAT's, by changing the fuel and map settings, timing, boost etc i'm quite sure he would be able to squeeze more performance than what he currently has.

Without being being able to revise the tune settings i remain skeptical whether he will ever be able to acheive any true performance gains other than be able to do more high speed WOT runs without getting the level of heat soak he had with the previous coolers in the hot summer weather.

Another interesting point is that the new .2tt coolers do not appear to be physically any larger in volumetric capacity than the .1 coolers. Im quite sure P has calculated the optimum volumetric requirements for the coolers in that application using those turbos and, running those boost levels....again remembering the engine is a set literage capacity.

The primary and sole function of an intercooler component is to cool the intake charge of air. Without cooling the air or lowering it to the temperatures that the tune is set for that component becomes useless and,superfluous. So, unless any Aftermarket cooler component can actually lower the intake air temperatures further than the stock item can its very purpose becomes highly questionable particularly particularly if it has gained in volumetric size. Any increase in the volume of air mass/space between the turbocharger and head ports can potentially create more lag unless the turbochargers are altered to compensate (ie push more air and, faster). So with stock turbos, installing larger intercoolers and, ones that are not as efficient in a cooling sense will result in a loss of sorts somewhere. I have read on these very 6speed forums certain users commenting that they have experienced an increase in turbo lag after fitting certain brand larger aftermarket intercoolers.

So, when you consider that many aftermarket coolers have usually gained in volumetric capacity/size, fitting a larger cooler without attending to the turbochargers may well result in a performance loss.....particularly if the cooler does not at least deliver the same temperature of intake air as the oem unit. One must remember that the intercoolers are just one link in the chain. Turbos, exhaust, ECU settings, fuel octane etc must all work in harmoney with one another.

Comments??

 

Im not sure if cost is a considering factor TT. The price differential may not be as great as one may think however i would safely say P's core requirements have been satisfied with that particular core design which is why they have used it. After all, flow and cooling must work in concert to satisfy the engines requirements. The other more "condensed cooling" type core, which appears to be more elaborate and accordingly restrictive" than the tube and fin design may well be more suited to a different capacity engine which may require that particular design core to meet the intercoolers size requirements and the space constraints for the cooler on the vehicle whilst satisfying the cooling and flow requirement for that particular size of engine.

Without understanding the mathematical equations behind these decisions it is easy for one to say one would be better used in place of the other however, the size of the intercooler, litreage/capacity of the engine, space constarints etc may possibly be key factors behind the manufacturers decision to select one core design over the next. Im sure if cost was the main factor for P then they would probably also use cast rims instead of forged, hancook tires in stead of Michelin or Pirelli and so on..

Edit: Incidentally the CMS cooler, which is larger in volumetric capacity than the oem .2tt cooler, may well have achieved a similar, or same, or even better IAT charge than .2tt coolers by way of using the denser turbulator core. Who knows as (surprisingly) no test has been done on that (yet). Actually, better make that very surprising given the cooling function of the cooler is the main reason why its even there in the first place. Then there is also the unknown aspect associated to the minimum/maximum flow requirements. EG why use a 6 inch water pipe to flow water to feed a 1'' outlet when 1 inch is all thats ever going to be possibly required (refering to cylinder and engine capacity).

OK. Possibly the denser turbulators would stall the air flow sufficiently to remove heat more efficiently but as that stalling effect is occuring over a significantly wider and larger core area any reduction of flow may not be felt at all (as evidenced by CMS's flow test comparison) as the flow is already more than what will ever be required (to correctly feed the volumetric cylinder capacity of the engine) due to the larger core capacity. Now, even though the (CMS) actual core flow is more than the .2tt cooler, that extra flow may not amount to a row of beans in a practical sense as extra flow was most probably not required....and, its yet to be proven it was required. Correct??

So, the only remaining loose wheel then becomes whether the additional volumetric capacity of the CMS cooler will alter lag levels where using a stock VTG turbo charger. It may well be that with a larger or modified higher flowing turbocharger the gain of the cooler air (but has to be same or less than oem .2tt cooler) is able to be put to good use without creating any additional lag from the extra volumetric capacity of the cooler core. I still think that using a larger cooler without combining a larger higher output turbo or modified stock VTG may well be a complete waste of time....and money for that matter.

Comments.

 

I think it boils down to optimizing the cooler for what the car will be used for. If you're a road/endurance racer & generally have some air going over the coolers, lower IATs at the expense of a reasonable pressure drop will take priority. If you're a drag racer or 60-130 kinda guy, having huge heat sinks with max flow potential is probably more desirable as some temp rise over the run is likely to be absorbed by the cooler's mass, so long as loading isn't constant for extended amounts of time. I've seen some logs from 4.5" coolers being killed by 3.5" cores in endurance racing so weighing heat sink ability vs hampering cooling airflow across the core by having it too thick is definitely something to be considered (when does your really thick heat sink that works great for a while start having issues with dissipation?). On the flip side, the 4.5" ers probably make more power for a single given pull until they're saturated (just a hypothetical example). The trick is getting a cooler that does both well

As far as B&P vs T&F in a flow & cooling sense, it doesn't really matter much. You can have crappy versions of either one as well a good ones. Generally speaking, T&Fs are lighter but more susceptible to FOD damage. Many 800-1000hp Supras run Greddy & HKS tube and fine cores with great results, many high hp domestics run Garrett B&P cores also with great results.

 

Did Skand actually post times or was that a seat of the pants observation? And don't you think performance could vary depending on ambient conditions?

His 60-130 time for stock turbo is so fast (6.4) that I have my doubts he could improve on that with .2 ICs or any other IC for that matter.

Amen.

I don't know. The .1 ICs are cheap and not very efficient. They could have done a lot better here.

I agree with much of what you say but those plastic end tanks look pretty precarious to me. They don't look like they're designed for high boost applications. I wouldn't be surprised if they even leaked a little.

 

At the present whilst it has yet to be proven that the .2tt coolers have a flow issue at high boost, flow becomes a moot point here....end of story. Any AM cooler must at least produce the same flow and the same IAT's as the OEM unit.....and, preferably better as that is the whole point why you would even bother going to the trouble and expense of changing them in the first place.

I personally think coolers are being given way too much attention and recogition when in fact it is most probably the modified turbochargers that are producing the bulk of or, all of the performance gains in many/ most cases. An attractive cooler is great and may give one a nice warm fuzzy feeling for all the dollars spent but unless you plan mounting them on the outside of the gaurds for the world to admire then it comes down to one thing: "do they really do anything over and above the stock units".

 

TT insofar as plastic end tanks and the like im sure manufacturing cost is involved to a point (as is weight). Im not qualified to comment there other than to say P would be the best to ask/answer those questions although yes i would agree that alloy end tanks appear more durable over the (very) long haul. But in saying that has there ever been one give way yet? That may well answer some of that question as im sure P put them to the test at higher boost levels to ensure a safety factor is provided for the product....which also ensures durability. Now with high boost from modding they may well not hold out as long over the "long haul" as what they would do under oem boost conditions. But again...where is the history of failures?

The .1 coolers were the first in the series so, were up for improvement along with the rest of the car during development and production of .2tt. It could be said P could have/should have made a lot of things better in the .1 car. To say the .2tt core design isnt up to the task is yet to be proven really.

Now with Skand. TT Id prefer not to comment if you dont mind . I would prefer if any questions about him are directed at him . You may recall my last experiences . But for all of that me and Skand i think are now on talking terms....well i hope so anyway. Now i would agree like yourself TT that i would be very surprised if he was able to do anything with the lower cooler IAT's other than perhaps pull sustained WOT runs without heat soaking as early. I think i pointed out in my earlier Post his APR tune has limitations.

And with performance, yes TT, agree totally that conditions such as ambient temps and so on all bare relativity to how an engine will actually perform to its optimum output. But again it has not been proven yet by anyone whether .2tt's coolers are unable to satisfy most operating conditions and situations.

I would agree that Karim, in 50 deg C temps is a very special case. But i note he is using Protomotive ceramic coated coolers and, has an adjustable softronic tune at present . His car is also PDK which retains constant flow of boost and pressure through the gear changes so there would be no momentary loss of boost or lag felt from the larger core sizes i imagine. It may well be a different story with a manual....i dont know....but we are talking Proto coolers here dont forget. Todd K is obviously an excellent mathematician to be a tuner (particularly at his level of expertise) so im sure he has all the answers worked out there too.