Heat Exchanger delete+oil cooler added

[Gelbster]

I am considering deleting the heat exchanger on my S and adding an oil cooler with a small fan.
Bilt Racing Oil Cooler Delete. For installing external oil cooler. Eliminates heat exchanger. M96/M97 only. LN Engineering
TRS Porsche Heat Exchanger Delete Plate – M96 M97 | TuneRS
This is an expensive project when you add in the cost of the oil cooler,fan and fittings.
My question is where is the best location for the small oil cooler+fan ? There are some obvious ugly locations that are fine for Racers but is there a discreet ,appropriate void somewhere to put an oil cooler on a Boxster.
And the 6 speed would benefit from an oil cooler also......
Thanks for any practical suggestions

[JFP in PA]

Originally Posted by Gelbster

I am considering deleting the heat exchanger on my S and adding an oil cooler with a small fan.
Bilt Racing Oil Cooler Delete. For installing external oil cooler. Eliminates heat exchanger. M96/M97 only. LN Engineering
TRS Porsche Heat Exchanger Delete Plate – M96 M97 | TuneRS
This is an expensive project when you add in the cost of the oil cooler,fan and fittings.
My question is where is the best location for the small oil cooler+fan ? There are some obvious ugly locations that are fine for Racers but is there a discreet ,appropriate void somewhere to put an oil cooler on a Boxster.
And the 6 speed would benefit from an oil cooler also......
Thanks for any practical suggestions

You problem is that to use an external heat exchanger, it would have to be larger than the oil to water cooler on the engine to obtain the same efficiency, and it would need access to outside (cool) air rather than engine bay air, which is already hot. You other consideration should be the oil pump; the stock cassette mounted pump does not have the necessary volume or power to move a larger volume of oil (new cooler and lines) long distances, so going to the front of the car is out.

Why are you considering replacing the compact and well functioning system you have now?

[Gelbster]

Thanks JFP .That makes perfect sense.
The warning about the pump is something I did not know.
Just trying to improve the overall cooling issues. I have to remove the existing heat exchanger to replace leaking oil seals ,so while I am in there I thought ...... But now you have simplified the task. Thank you.
The new seals I fitted to the HeatX after the rebuild have failed already ! So I hope the ones from Pelican perform better than those that came in the rebuild kit of seals..

[steved0x]

If I ever do an oil cooler I would probably go with the Mocal thermostatic sandwich plate coupled with a derale scoop cooler (if I can find a spot under there) or else the derale hypercooler with fan pack with possibly a duct to pull cooler air from somewhere, maybe under the car. Keeping the OEM heat exchanger in place. Short lines so hopefully minimal pressure loss. However my oil temp, as measured in the left valve cover, mostly stays between 200 and 220 (at Roebling in the 70's it gets to 210-215 by the end of a 20 minute session) and on tracks that are a lot full throttle (Sebring and the FIRM for me in July) it will get over 220 by the end but not to 240, and I have never been over 240F.

Oil.pressure for me starts to go down (as observed on my videos around 210 or so), if I got a cooler it would be to try and keep my oil closer to 200F to minimize pressure drops during cornering.

[flaps10]

Why are you considering replacing the compact and well functioning system you have now?

I've always thought it would be cool to replace the rear spoiler with an external oil cooler that moves into the airflow as needed based on thermostatic needs.

Seems almost too easy.

[JFP in PA]

Originally Posted by Gelbster

Thanks JFP .That makes perfect sense.
The warning about the pump is something I did not know.
Just trying to improve the overall cooling issues. I have to remove the existing heat exchanger to replace leaking oil seals ,so while I am in there I thought ...... But now you have simplified the task. Thank you.
The new seals I fitted to the HeatX after the rebuild have failed already ! So I hope the ones from Pelican perform better than those that came in the rebuild kit of seals..

Get the factory seals, they are cheap and we have never had one fail on us.

[JFP in PA]

Originally Posted by steved0x

If I ever do an oil cooler I would probably go with the Mocal thermostatic sandwich plate coupled with a derale scoop cooler (if I can find a spot under there) or else the derale hypercooler with fan pack with possibly a duct to pull cooler air from somewhere, maybe under the car. Keeping the OEM heat exchanger in place. Short lines so hopefully minimal pressure loss. However my oil temp, as measured in the left valve cover, mostly stays between 200 and 220 (at Roebling in the 70's it gets to 210-215 by the end of a 20 minute session) and on tracks that are a lot full throttle (Sebring and the FIRM for me in July) it will get over 220 by the end but not to 240, and I have never been over 240F.

Oil.pressure for me starts to go down (as observed on my videos around 210 or so), if I got a cooler it would be to try and keep my oil closer to 200F to minimize pressure drops during cornering.

Again, the problem is size. Oil to air coolers have to be larger than oil to water coolers, just to be equivalent in heat exchange capacity.

[The Radium King]

997 oil cooler has the same footprint as your oil cooler but is 15 mm taller - perhaps wedge one of those in there.

[Gelbster]

Originally Posted by steved0x

If I ever do an oil cooler I would probably go with the Mocal thermostatic sandwich plate coupled with a derale scoop cooler (if I can find a spot under there) or else the derale hypercooler with fan pack with possibly a duct to pull cooler air from somewhere, maybe under the car. Keeping the OEM heat exchanger in place. Short lines so hopefully minimal pressure loss. However my oil temp, as measured in the left valve cover, mostly stays between 200 and 220 (at Roebling in the 70's it gets to 210-215 by the end of a 20 minute session) and on tracks that are a lot full throttle (Sebring and the FIRM for me in July) it will get over 220 by the end but not to 240, and I have never been over 240F.

Oil.pressure for me starts to go down (as observed on my videos around 210 or so), if I got a cooler it would be to try and keep my oil closer to 200F to minimize pressure drops during cornering.

I am not trying to talk myself into a (needless-thanks JFP!) project but for sake of an interesting discussion -
Flaps has an interesting proposal .It is an outa da box solution to the lack of space for the cooler.
But if you fit an oil cooler,wouldn't the water cooling system benefit if you removed oil cooling from it's list of tasks ? Surely you wouldn't want to keep the heat exchanger and do an oil cooler? The 2 HeatX delete plates I linked above do not offer that option anyway. And then there is the gearbox oil cooler to find a home for. Maybe Flaps would have both in the existing spoiler side by side?

[Gelbster]

Originally Posted by The Radium King

997 oil cooler has the same footprint as your oil cooler but is 15 mm taller - perhaps wedge one of those in there.

Pelican has a project for that but mentioned that it may/may not fit. I did not understand why they waffled on the fit. They did confirm it is substantially taller.It is tempting because it seems an easy substitution - if it fits under the Bank 2 intake.

[specboxCO]

If the coolant system is working as it should, it has way more capacity to remove heat from the oil than is needed. If you have an overheating issue, it is almost 100% on the water side. There is no need at all for an external oil cooler.

[Anker]

Have you cleaned your radiators?

And if you don't have a S, consider mounting a third, central, radiator.

[thstone]

Some Spec Boxster's use the space behind the rear wheel (where the stock muffler U-pipes turn) for external radiators. Of course, this means that you would need to have straight pipes so the U-pipes could be removed to free up the space.

Take a look at a few of these images to get some other ideas... Boxster Transmission Coolers

[Gelbster]

Wow ,that is a great link to lots of photos.
I just removed my Heat Exchanger (Boxster S) that was leaking oil ,not coolant.The leak was all over the top of Bank 2 - recently cleaned !
I very carefully measured the "O" rings - the leakers are slightly thinner and harder than the replacements just bought from Pelican.

[JFP in PA]

Originally Posted by Gelbster

Wow ,that is a great link to lots of photos.
I just removed my Heat Exchanger (Boxster S) that was leaking oil ,not coolant.The leak was all over the top of Bank 2 - recently cleaned !
I very carefully measured the "O" rings - the leakers are slightly thinner and harder than the replacements just bought from Pelican.

Be careful about where you source these O-rings; a lot of aftermarket stuff is not up to the task, and start to leak. We stick strictly to the factory rings as they are cheap (if memory serves, last time we bought a bag of each, they were about $0.50 each), readily available, and do not fail shortly after being replaced.

[Gelbster]

Thanks for chiming in JFP.
The leaking 'O' rings were supplied by Parts Container as part of a kit. The replacements are from Pelican .When I removed the heat exchanger the bolts were tight and the seals looked perfect. Dimensionally they are suspect and they 'feel' different(durometer?) from the new Pelican parts. The engine has zero miles - just test run.
After I position the new Pelican 'O' rings on the engine ,I'll use a straight edge and feeler gauges to measure how proud they are of the mating face of the crankcase. Odd that the stock spec calls for 4mm thick coolant rings but thinner 3mm oil rings. I suspect the measuring is irrelevant. Durometer is probably the issue which is difficult to test empirically diy. And then there is the material choice-HNBR,Viton.Buna(I hope not!). Hence buying from Pelican and trusting them.I presume it is verboten to use any sealer?
Here are the part numbers for the convenience of others.
999-707-389-40
999-707-409-40

[JFP in PA]

Again, I will suggest caution on where you buy these O-rings.

[WorkInProgressK]

Originally Posted by Gelbster

Thanks for chiming in JFP.
The leaking 'O' rings were supplied by Parts Container as part of a kit. The replacements are from Pelican .When I removed the heat exchanger the bolts were tight and the seals looked perfect. Dimensionally they are suspect and they 'feel' different(durometer?) from the new Pelican parts. The engine has zero miles - just test run.
After I position the new Pelican 'O' rings on the engine ,I'll use a straight edge and feeler gauges to measure how proud they are of the mating face of the crankcase. Odd that the stock spec calls for 4mm thick coolant rings but thinner 3mm oil rings. I suspect the measuring is irrelevant. Durometer is probably the issue which is difficult to test empirically diy. And then there is the material choice-HNBR,Viton.Buna(I hope not!). Hence buying from Pelican and trusting them.I presume it is verboten to use any sealer?
Here are the part numbers for the convenience of others.
999-707-389-40
999-707-409-40

The issue with sealer on the oil side is contamination post oil filter and pre oil passages. As the silicone doesn't really degrade in oil and block passages.

What you could use is grease made to swell rings. Done right you shouldn't need any sealant. One other issue with sealant is that it takes a good .010" to .020" of space when done right, which would be bad for the O-ring interface.

HNBR is probably your best choice.(green rings sometimes black). Black rings are probably NBR which aren't bad, just not as good as HNBR.

[Gelbster]

The Pelican rings are HNBR.
Thickness mystery solved.The annular grove for the coolant seal is 3mm. For the oil is 2mm. So 1 mm of compression to seal. Hence the importance of the thickness dimension I mentioned earlier.The Parts Container oil "o" rings are too thin !Yes, they are thinner than the specified 3mm. The Pelican part is a full 3mm.
Just like JFP said , the OEM seals worked perfectly. The ones from Parts Container leaked immediately. The issue was below spec thickness of the oil "O" rings from Parts Container. As I mentioned ,these came as part of a large engine rebuild kit that I used. Now I am wondering about the other seals and parts. The Heat Exchanger seals was a relatively easy fix. Other parts would be much more difficult and potentially destroy a newly rebuilt engine.
To be clear, the issue in this specific case was not HNBR/Buna/Viton. That is only because the engine has zero miles. The oil seals leaked when the engine started for the first time after the rebuild.And yes, of course the 4 bolt were torqued correctly and the base of the HeatX is flat.
As my measurements above showed, if you have an undersized thickness of the "O" rings and the factory machining allows for a max of 1mm of seal compression, it will leak. I was lucky to catch it before any damage occurred.
I hope this helps others with the same issue or choices in sources for seals.

[Smallblock454]

HNBR is the only way to go for that application.

Regards, Markus