I think there would still be a market for a quality IC geared for road course use as there are still a good number of guys that track these cars and spend a ton of money doing so. I would be willing to spend $3-4k on a set of ICs if they were proven to be better than the 997.2s, which certainly have their limitation. I suspect that the type of core and design of the IC as a whole would need to be geared more towards fast thermal recovery rather than ultimate flow. Maybe a slightly larger core than the 997.2s but one that is just as dense. Does anyone produce an IC that has the same aircraft grade quality core with the same fin density as the 997.2s? I know vendors are reading this so feel free to chime in. Anyone? It seems all the AM coolers have a core that is much more coarse to facilitate more flow at the expense of thermal recovery.

 

obviously this forum is more geared towards straight line 1/4 mile and up racing. so more flow the better. for road racing i don't think theres much better than the 997.2 after reading earls threads. it wouldn't hurt for you to drop itguy a line. his cores are custom made to his specs so he might have some input regarding what your looking for in a large i/c. he is very knowledgable and always open to someones ideas to make a better product

 

I'll give Sean a ring to see what he thinks but as far as I know all of his experience is with the high hp straight line stuff also. There are a number of vendors here that offer very good IC options for the short duration high HP 900+ guys but no real option besides the 997.2s for the 600-700 track guys. Ultimately I'd like to find something that offers even faster thermal recovery than the 997.2 units. Maybe there is no such IC and the 997.2s are as good as it gets. Maybe that's the case. After all Porsche developed and tested these for hard core track use at the rink. This past weekend I ran over 250 hard track miles in ambient track temps at well over 100F, likely 115+ as temps in the shade were 97F. After about 8 laps (15 minutes of running at the limit) I saw IATs creep up to 160F at 140mph and drop to about 120F when off throttle under breaking. I would say average IATs were around 140F when fully heat soaked and I could definitely feel the boost taper off to 1.0bar after 6500rpm when I normally hold 1.2-1.3 bar all the way to 7500. I would still love to know if a better performing product could be manufactured, maybe one that would keep IATs another 10-15 degree cooler than what I'm seeing with the 997.2s.

 

Sean shared some data with me, straight line numbers, with the stock intercoolers. It was very very ugly! The cores heat soaked real fast and I'd honestly be real surprised if the 997 cores did better. I like the idea of running different cores per side and instrumenting them, it would sure put this to rest. My driving is all street and getting the space to do a had run is getting hard around here. I'm going to be pretty interested to see how his hardware stands against the Heat and humidity here for sure!

 

typical IC cores seen in this after market world have .2mm fin thickness, 2-2.5mm pitch and 7-10mm external row width. This design provides a certain degree of efficiency. There are other options available, one of UTC's subsidiaries makes high efficiency aerospace cores, however you are into the 1000$+ per core. I could make a stupid high efficiency 3.5" core for road racing, but no one would buy it due to cost. Prove me wrong and buy one

 

These are the threads I like to see on this forum!


I had the 997.1 intercoolers prior to the 997.2 or (997.2GT2rs Intercoolers.) 997.1 just plain suck.


I recently ran at the same track with similar temps as pwdrhound. I experienced virtually no lag. I also was running E85 (E90 measured.) BTW pwdrhound, you were the only one that passed me this weekend! Your car is strong as hell.


Back on topic,


Don't know if it is E85 or the intercoolers that resolved my heat soak problem I had last year.. I have the 997.2 GT2RS intercoolers installed. Engine does feel cooler to the touch in comparison to my 100oct. setup last year.


Here is my past weekend with similar conditions,


I hit 211.55F IAT's, and this temp was at 148mph. Ambient air at this time was 88.7, It was actually 92.75 degrees right after starting the car. Yahoo! weather stated 96F.


Starting IAT's during this run were at 113F. Heat soaked temps were at 125F prior to moving the car.


Logging at the track was very nice with the access port with Cobb. One button, solid state, and can change tunes on the fly.

 

E85 doesn't mind the IAT's you saw. The touching engine thing is really in your head though, maybe invest in an infrared thermometer and test both fuels for some solid data. E85 is really the savior here.

 

Infared in which manner? I have both photo and laser measurement devices from Fluke. I do agree on having more solid numbers for ambient engine temps with focus.. I will keep this in mind next time I am at the track.

I made the hand test attempt at the track with a similar car running 91 oct... Couldn't hold my hand on his intake while, I could sleep on mine.

If E85 is the savior due to its cooler combustion, do you think I could run with the 997.1 intercoolers and have similar temps? When reviewing my logs, my intercoolers seem to have a nice effect on the temps once the throttle is off the floor.

 

it's not uncommon for some cars to run e85 without intercooler, as long as the tune isnt pulling a ton of timing solely for intake air temp, I suspect you could put the stock ic's back on the car run the same (or very close) times.

One of these


Would be cool if you and your friend with ****ty ic's could run around the track on the same fuel, and same speed etc, then stop and measure both intakes with the above device quickly.

 

Word. I've gone through a lot of intercoolers now on my car to include 4.5" Bell and CMS 2010+. Guess which ones are back on the car on account of overall performance vs recovery time? ...I have a hunch there's a reason you don't see the type of data you requested. It costs ~1500 to know everything about an intercooler in a controlled environment.

The next step are CTR w/ Marston cores. They do a "budget" option for around 6k which are approx 2% more efficient than .2s (under controlled sustained loading). Fernsport looks interesting as well.

1/4 mile or 60-130 (or a dynojet) is nowhere near enough to thermally load a cooler. Buy the highest flowing option and run a meth nozzle

To the OP, no, 997.1s are not a worthwile upgrade over stock 996.

 

I'm guessing you are back on the 997.2s Earl. Thanks for chiming in by the way. You are the foremost authority on ICs here as you have done more with regards to "scientific" testing than anyone else here that I know off. Honestly, $1500 for testing is not very much when you are talking about a product selling for $2-3K. I would be nice to do a direct comparison of the various ICs out there. The way to do it would be to mount up the benchmark 997.2s on one side of the car and then compare them to other makes on the other side of the car. This way, you would be doing a direct apples to apples comparison under identical conditions. Run several types of tests, a 1/4 mile blast, a 40-150 pull, and then a 15 minute continuous session of laps at the local track. Doing it like this would be the only way to get real world data and it would not be that expensive to do and the results would give people an idea of the performance under their particular type of use. Every vendor on here could supply a single intercooler for the test which would be returned at the conclusion. Those that wouldn't would obviously have something to hide.

Based on what I'm reading above, there really is no better option out there that the OEM coolers for a track application. $6K cores that provide a measly 2% increase in efficiency just don't make sense. If it was a 10% increase, then maybe, just maybe. I remember reading your thread from a while back comparing the ETS coolers which provided some short term gains over the 997.2s but were on even ground after a single long pull. I would imagine that the 997.2s would be ahead of the ETS within a minute of continuous hard use as the heavy ETS's would heatsoak. On top of that, the ETS coolers were about 20lbs heavier for the pair if I recall. Since then, I haven't really heard of any other viable options.

Keep up the good work Earl!

 

Hey brother. Good running with you this past weekend. This was probably the hottest couple of track days we've had in a couple of years. I wanna see that log. 211.55F IAT is almost 100C. That is crazy high!!! It's almost hard to imagine the car could run well at such high IATs. Must be the high octane of the E90 fuel. Incidentally, 211.55F is also much higher than the top IAT's I saw. I didn't log but my IAT gauge showed in the 160s at the hottest. That is still 50F less than what you had. Interestingly, my heat soaked temps were at 153F prior to moving the car, so 30F higher than yours. This goes to show how much cooler the engine is burning E85 as your engine compartment temps are so much lower. Your intake manifold is substantially cooler to the touch than either on my car or the other 997TT there. I could barely keep my hand on those. Doing a simple touch test does not lie.

Ultimately, I'd like to see our data and performance comparison while running the same fuel. You are effectively running 116 octane fuel while I'm on 93-95 octane. Actually, if it's E90 measured then it's probably higher than 116. It would be interesting to see how your car would perform on the lower octane fuel I'm running. Conversely, I could try to run straight 100 or 110 to see if the car does, but it still wouldn't be E85. I think the conclusion is that IC's performance might not be quite as important when running E85 as it is when running normal pump gas.

Thanks again for lunch Saturday!

 

+1 for Earl. There is always something to learn.

I think it's pretty safe to say that no one cooler is perfect or fits all applications. Several tuners have seen the gains and support larger intercoolers from the .2's with their greater mass, flow and cooling ability. Not to mention ability to hold/flow at higher boost and power levels. With larger units you get a natural slower recovery than the light .2's and their plastic end tanks yes. I think for John's boost/power level, use and all things considered the .2's are a great option after you epoxy them. I have road raced with a few good AM 3.5's and seen the +/-'s they have to offer. I like them more over-all and the tuners seam to also. Boost level and set-up makes a huge difference here. Lastly, remember many reputable companies have been making great coolers for years before and after the .2's came on the scene. It always depended on application.

 

One of the Audi enthusiasts built a flowbench and had all the intercoolers sent in for testing. http://www.myaudis4.com/intercooler-faceoff/

He would be happy to do it again for anything we send him provided shipping is covered. If anyone has a 997.2 side that could be sent in, i'd like to compare mine to it cfm wise.

 

CFM is one thing but only a part of the equation of overall performance. I would think that pretty much all of the 4"-5" ICs will flow better than the 997.2s, but what about thermal recovery. How would a flow bench replicate heat soaking and recovery Sean? I'm assuming you could flow a certain CFM of air set to a specific temperature though the cooler for a certain amount of time (say a couple of minutes) while the core is being cooled externally via a controlled amount of air? I assume you could alternate the amount of air flow though the IC to replicate on / off throttle for maybe 10-15 minutes.

It would be great to see some unbiased results.

It still seems to me that an "on the car" test like Earl has done in the past would be the most accurate way of evaluating real world performance. It couldn't get more accurate than that. The only difference would be to use one side used as control while the other side is the test.

And yes, I agree with Sambo. Different applications require different IC designs. Just wish there were better option for my type of operation.