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At 83 mph avg on my way the the Amelia Island Concord in 83F weather, my oil temp averaged 236F. That seemed a bit high to me. It seems like more oil cooling would be a good idea, but the middle radiator slot is blanked off, unlike the early Boxster S.
 

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BTW, 194 F water temp is not an idiot setting. It is the water thermostat calibration. It seems to me, as an engineer, that an additional water to oil intercooler would be useful to both speed warm-up and reduce high oil temperatures. These cars seem to have plenty of radiator water cooling, but are a wee bit short on oil cooling. An oil cooler could also work but IMO would need a thermostat because they are already slow to get the oil up to operating temp. It takes me at least 15 minutes b4 my oil temp is high enough to exceed 4500 rpm. I try to hold it down to that level until my oil temp is about 190F every time I drive it, per my manual. It is a real bummer having to wait 15 minutes. An oil cooler without thermostat would extend the warm-up time significantly and that would be unacceptable to me. What is available in the aftermarket for reducing high oil temperatures without increasing warm-up time?
 

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At 83 mph avg on my way the the Amelia Island Concord in 83F weather, my oil temp averaged 236F. That seemed a bit high to me. It seems like more oil cooling would be a good idea, but the middle radiator slot is blanked off, unlike the early Boxster S.
That sounds about right. If you had put it in Sports or Sports Plus, you would have seen oil temps drop almost immediately.
 

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BTW, 194 F water temp is not an idiot setting. It is the water thermostat calibration.
actually it is an idiot setting, when pulling the values from the ODB or CAN bus, you will see the water temp higher then 194, even when the gauge says 194.
 

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Has anyone measured the effect of removing the a/c condensers and/or adding a splitter and what that does to improve air flow?
I have been told by several people that a splitter will help, but adding the splitter also necessitates adding the rear spoiler, which is something I don't want to do yet.
It's hard to tell if the GT4 bumper has larger openings, but they certainly look as if they are designed to capture more air and the addition of the center vent should also improve air flow.
I will find out later this summer if adding the third radiator and the oil/water exchanger for the diff. will make a difference.
I have heard the same things a John about today's oils being so much superior that they can handle these temps. But unlike the NASCAR people, I cant afford to rebuild my engine every weekend and I still believe that heat is the enemy of all things mechanical.
I'm with you 100%; just because it doesn't mean it's going to hurt the motor, does not mean we want to sit there and live with it. Removing the condensers, adding a center 3rd radiator and upgrading to a more purpose built motorsport style aluminum radiator with a higher end core and better cooling fins will significantly reduce temps; wrapping the exhaust manifolds to reduce the ambient heat they produce in the engine bay will further these gains. Adding a splitter may help a little bit but not as much as confirming that you have good air flow to exhaust from the backside of the radiators. We have even gone so far as to cut holes in the front part of the wheel liners and put grills in them to speed up the exhaust of the hot radiator air. Sure it puts it in the wheel wells but the net effect of giving that hot air a place to go pays dividends! Since the ducts on the intake side of the radiators are more open since they don't have the foglight issue that the 987.2s did, there isn't any upgrading to do here.

P.S. One of the biggest reasons I gave up on the oil heat exchanger project and designing a front mounted air-oil cooler setup to run to/from it is that it's not as easy to mount a cooler up front as it was on the 987.2 and furthermore, I was always afraid of introducing angles and bends at the filter housing to draw/deliver the oil and certainly putting anything in between the oil filter housing like you see on some cars spooked me. The reason to use the 997.2 style exchanger was because it's plug and play and a tried and tested Porsche part that we have analyzed with the upgraded radiators from PWR on the 987.2 cars that have been reduced to under 192 on the water and 230 on the oil. We were sort of embarrassed when we built that Cayman R last summer when it wouldn't last more than 25 minutes on track in 95 degree ambient temps before I kept pulling him off because of high oil temps. I have no doubt that the upgraded radiators and upgraded cooling would reduce oil temps substantially.
 

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actually it is an idiot setting, when pulling the values from the ODB or CAN bus, you will see the water temp higher then 194, even when the gauge says 194.
Yes, you are correct. Mine temp was reading 220 Degrees.
 

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John, with the addition of two 997.2 radiators, and a 981 Center radiator will this equal the amount of extra cooling you got on one of your cars to get the oil and water temperature so low.
 

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Different fender liners can be added as seen in these pictures or maybe doing surgery to our already present ones to open them up a bit should help the radiators. Notice also the additional brake ducts and the part numbers below.

070.jpg 071.jpg

Fenders - 99150450194 and 99150450294 (these liners are screened)

Air Deflectors - 99157513181 and 99157513281

Thank you futurz for the pictures and part numbers. I grabbed them off one of your previous posts.

This should all help with brake cooling as well as the overall cooling of the car. There will be more air flowing through the radiators with less outflow restriction, and more of it directed at the brakes. Even though the air will be 200+ degrees, that is still a lot cooler than the brake calipers and rotors while on the track.
 

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John, with the addition of two 997.2 radiators, and a 981 Center radiator will this equal the amount of extra cooling you got on one of your cars to get the oil and water temperature so low.
@LovetoTurn - In order to be apples to apples, you would have to:

1.) upgrade all 3 radiators to PWR spec (i'm not sure if they make one for the 981 center radiator but i can check).
2.) upgrade to a better flowing front and rear fender liner like what is shown above
3.) upgrade the existing oil/heat exchanger on top of the motor to 997.2 spec

Do we have any folks local to us that are grossly concerned about oil temps that would be willing to allow us to use a real life example or would I have to do everything to my street car and document it? PWR recently acquired C&R radiator but the new regime was very open to making a larger 997.2 style heat exchanger. I'm currently trying to figure out how big we can go and still clear the 981 3.4L intake manifold.
 

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Thanks BGB, so a center radiator will help a little, but to get that kind of cooling upgrade will require some major additions to the cooling system.
 

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It's my goal to find a solution that isn't "major" but I know that some things will deliver no matter what config you run. Removing condensers would help but I would assume not many of you are willing to give up your A/C; I know I can't. I will start today on a project to reduce oil temps in my street car to see what we can achieve.


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I'm with you 100%; just because it doesn't mean it's going to hurt the motor, does not mean we want to sit there and live with it. Removing the condensers, adding a center 3rd radiator and upgrading to a more purpose built motorsport style aluminum radiator with a higher end core and better cooling fins will significantly reduce temps; wrapping the exhaust manifolds to reduce the ambient heat they produce in the engine bay will further these gains. Adding a splitter may help a little bit but not as much as confirming that you have good air flow to exhaust from the backside of the radiators. We have even gone so far as to cut holes in the front part of the wheel liners and put grills in them to speed up the exhaust of the hot radiator air. Sure it puts it in the wheel wells but the net effect of giving that hot air a place to go pays dividends! Since the ducts on the intake side of the radiators are more open since they don't have the foglight issue that the 987.2s did, there isn't any upgrading to do here.
+1 on the exhaust wrap. The C7 corvette has had some issues reported by drivers at the track--especially the automatics--with high temps in the transmission/differential.
One reason is that the exhaust wraps around the tranny raising temps, despite having transmission coolers.Reports I've seen on forums is that the wraps around the exhaust have helped reduced temps.
 

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+1 on the exhaust wrap. The C7 corvette has had some issues reported by drivers at the track--especially the automatics--with high temps in the transmission/differential.
One reason is that the exhaust wraps around the tranny raising temps, despite having transmission coolers.Reports I've seen on forums is that the wraps around the exhaust have helped reduced temps.
Agreed. It all adds up after a while and eventually A+B+C+D will equal !


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What's the best product for wrapping the exhaust?
After talking with John and a couple of other folks, the next step for me if I continue to see high oil temps will be to remove the AC condensers. I never use AC anyways and the car is now being trailered to the track. I should know by the end of June at the latest what the verdict is.
 

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Was planning to use DEI titanium exhaust wrap on the over the axle pipe on the new exhaust. This should keep things a bit cooler, a bit quieter, and maybe even dampen the exhaust slightly. Anybody have any problems keeping this stuff on the cars exhaust tubing. Was thinking of using two exhaust clamps to hold it in place. Shouldn't go anywhere with those things binding it to the pipes. Maybe wrap the pipe all the way to the muffler?
images.jpeg 010475-TitaniumProtectaSleeve-front.jpg Unknown.jpeg

Maybe even wrap the mufflers in in this kevlar and foil stuff.

Screen Shot 2015-04-08 at 6.19.56 PM.jpg

Maybe this is all too much wrapping, but I know another forum member wrapped his Borla with the kevlar and thought is was bit quieter and certainly would be a little cooler for the engine as well.
 

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....... but I know another forum member wrapped his Borla with the kevlar and thought is was bit quieter and certainly would be a little cooler for the engine as well.
Why would it be cooler for the engine?
The cans are behind the engine, right? If the car is moving, the heat is naturally dissipated away from the engine, wrap or not. Right?

It's okay, go ahead and give me lesson in thermal dynamics that wasn't part of my business curriculum. My science electives were oceanography and zoology.
 

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Had an extensive conversation today with my dealer tech and the service mgr. about the cooling issue.
FYI - Everything I say here is about the 981S which is what I have. Can't and won't speak to any other model.

The 981 manages its cooling from the ECU, not a mechanical thermostat.
Porsche has programmed minimums and maximums into the system. As far as I know, no one has been able to document exactly what those parameters are because we can't get into the ECU.
No amount of cooling is going to bring coolant temps below that minimum.
Apparently, the maximums are higher than many of us are comfortable with.
The way we find out what Porsche's maximum is, is by the car going into limp mode.
It seems both apparent and logical to me, that our (my) goal should not be to get the car to run at some arbitrary lower value, but rather, to try to prevent the car from exceeding it's maximum thresholds.
If we can successfully mitigate against the worst case scenario (limp mode) more than likely, the car will be running somewhat cooler than it otherwise would have been.
For the record, my car has never gone into limp mode, even on the hottest day at HPR and that was before I added the third radiator or the Laminova exchanger for the diff.

My course of action to try and achieve the goal above:
1) Add the third radiator which John has been preaching all along. Done.
2) Because I installed the Guard diff. which generates more heat, and because the diff., due to it's proximity to the tranny (PDK), acts as a heat sink, I installed the Laminova.
3) We believe the car now has enough exchangers in play to dump oil heat into the coolant. The question is, will the three radiators be able to get rid of all that heat?
4) The next step if necessary, will be to attempt to increase air flow through the radiators. Since I don't drive my car on the street anymore, I think getting rid of the condensers which sit in front of the radiators, and perhaps even removing one of the fans, might just do the trick. John showed me a picture of just how much real estate those condensers take up. As has already been referenced, I have installed the more open GT3 fenderliners which should help with air flow as well.

I am going to go as far into this season as possible without resorting to #4. I will be monitoring both coolant and oil temps. Of course, if the car should ever go into limp mode, I will have no choice but to implement step #4.
If that doesn't work, than I am looking at a total overhaul of the front end of the car, perhaps by adding the front bumper and cooling vents from the GT4. But I think (hope) that drastic step can be avoided.
Stay tuned....
 

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Well I have a medical degree, so I am no expert here either. However one of the most basic principle with heat is that it rises. Yes the air passing under the car will cool everything down to some degree, but some of that heat will escape and rise off the upper end of the mufflers and heat the top of the engine chamber. When you are at a stop on idle, all the heat will rise and be contained in the engine chamber as well. I doubt it makes a huge difference to do this, but it costs less than $100 for a sheet of this stuff and it may be worth a few degrees for someone having problems with their car. Looks like a simple weekend project for the DIYers, that have an after market exhaust.

As we can see by the comments in this thread no one upgrade can solve the heat issue in the extreme cases. So it will be a combination of a number upgrades depending how much time you spend at the track and where you live. A third radiator seems like a good place to start for most of us that live in the south, and this is Porsches own answer for cars destine for the middle east.

John, was wondering about DEI titanium wrap for headers and or exhaust pipes? Cobb Tuning uses it with their turbo upgrades. Does it stay on for the long haul or is it just a pain in the butt.

Thank you futurz for all you input on this subject. Looks like you are blazing the trail for the rest of us.
 
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