Yeah, the muffler delete seems to be the most cost effective spot. LN had built a kit using the bigger cayman cooler to put it there for the 996. Don't know if it's still available.

Some have discussed a sausage shaped cooler to sit somewhere near the trans which has some room.

Using the center radiator space would be convenient. Jake had discussed building a couple of these for the 996 as did CTS for the boxster/cayman. Cost may be crazy silly.

 

You can still use coolant to sink heat from the oil, and reuse the original oil cooler if you weren't having oil temp issues to begin with; just gotta relocate it away from the engine a bit. There's a pocket near the trans (in front of the rear axle line) that I think is pretty empty from the factory.

If you wanted to use an air-oil exchanger it would be most effective at the front bumper by far, but if you don't need too much cooling (even 100F air cools oil better than 180F water) it could go anywhere you find some space in the undercarriage. The center tunnel is pretty underutilized, maybe a duct with a fan for forced-air somewhere near the green arrow?

 

Buy a Gen 2 997 S or Carrera (if you’ll be satisfied with a 3.6 996.2, you’ll be more than satisfied with a 997.2 3.6 Carrera, and it’ll be all the 911 you’ll need, without the many and varied issues that afflict the M96 engines.

The S85 V10 is like the S65 V8, have the rod bearings replaced with additional clearance items, then do frequent oil changes using good quality oil, use the car frequently and have the throttle actuators rebuilt.They’ll do well over 100K miles without breaking sweat.

 

Your just suffering from " Technical Overload" ..you need to take it small bits ....All cars, every engine, is starting to fail every moment ( not a nice thought, but some of us are into counter-actions of the obviously inevitable)and when we dive deep into the Technical why's/when's It can be overwhelming if you are not used to it, so take it in small bits.. You'll be stronger/happier/knowledgeable in the end...

Great discussion guys!!! Loving all the thoughts and participation..Heading to the store for a bit, be back shortly to further derail this thread...( after all this is a "Technical Forum') , so sorry/not sorry for the hi-jacking...

 

I don't totally agree with this. The heat capacity of water is so high it actually cools well even at 180F. It's needed to keep the water cool of course and the 2 tiny radiators on C2/C4 are not always up to that task.
I have an air/oil cooler for my transmission and I mounted the heat exchanger where the front diff used to be. There are handy NACA ducts in the underbody covers already. This does a great job keeping the gear oil <180F as long as the car is moving and I added some moped radiator fans (really!) for when the car is stopped.

 

Specific heat and thermal conductivity of water are great, yes, but water/oil is never getting to the point where your (air) Setrab overcools the oil under operating temperature and drags down the coolant temps with it. Air/oil coolers usually need thermostats to avoid overcooling; water/oil just brings the oil back down to near-water temp (this is a good thing, I'm not knocking it) at the expense of needing more heat rejection from the water. That was the point of my comment to begin with - the factory cooler can still be used just fine, just relocated somewhere else to avoid heating up engine Bank 2.

I'm not sure if C2's have enough space up front, all I see is water pipes in the tunnel and a fuel tank in the way.

 

@thatg , sorry man. Threads sometimes go down paths that derail the original intent of the threat. No harm was intended, but this is an interesting topic on prevention of bore scoring through cooling procedures that gets some of us fired up.

First of all, I hope everything checked out with the 996.2. As I said before, they are great cars and I would not want to get rid of my 02 after owning it 22 years. Yep, the engine is in great shape, but eventually I will get it rebuilt once I figure out all of the bells and whistles I want with it.

Second, every issue we have discussed on your thread is easily preventable with the proper parts and procedures. I don't loose any sleep. We have more solutions than what we know what to do with.

Third, all you have to do is find a 996 that's been taken care of and the PPI and Bores check out. Then run the best oil you can find and change it often. Don't be afraid to put it thru its paces as well. Contrary to what you may think as a byproduct of all the discussions on each thread, the 3.4 and 3.6 are very durable engines. I started tracking mine in 2004 and am still tracking it.

Yeah, cooling isn't an issue unless you track the car at tracks with alot of long straights on very hot days. But many of us are always looking for more of everything: oil, cooling, grip, handling, brakes, engine durability, etc. You get the idea.

Enjoy the 996. It will be worth it.

 

After reading through this thread I am literally never going to sleep again. I will lie awake at night wondering what will go wrong next, and how many reasonably priced houses it will cost to fix. Thanks guys!

 

I ordered the stomski adapter
this is a great thread I believe you can never have enough prevention especially for the m96 engine

 

Ok back from the store and ready to derail this thread some more , BTW who started this hi-jack? anyway it is a good drift...



It is a bit of a conundrum, exchanging the 996 oil heat exchanger for the larger 997 oil heat exchanger will lower the oil temps and help keep from spinning a rod bearing, but places more heat load on the bank 2 so it would be wise to increased the cooling capacity of the cooling system with a center radiator or bigger CFS radiators or both, to have a win -win with no detriments...

It all about heat transfer/management in this case. In my 50 years in the business I have NEVER seen a properly built engine fail due to being too cold...Whether its a street engine , a race engine, an endurance engine, marine engine....they always fail from thermal runaway, or lubrication issues, or over-stressed parts...

Marine engines typicaly run about 160F operating temp..and do it at wide open throttle all day long, every day...But they have plenty of nice cool WATER to run in, they have to "make" the engines get up to 160F just to get to operating temps.....Road cars have to rely on AIR to transfer the heat energy made from the combustion chamber...If we could keep our engines temp to 160F, it would solve ALL the issues ( just about)....lol

Laws of Physics State that Heat Energy will always seek to transfer to a cooler area/substance...

You can do it,you got a dyno, just need a mule engine and drill a bunch of holes in the heads and block and install sensors....then collect the temp differences...you will see how much hotter the bank 2 runs than the bank 1.

Jake did this years ago , but never published the numbers , I don't know if he does any mods on the cooling systems( probably not), when you reconstruct all engines with Nikasil, no need to improve the cooling as much, the Nikasil is more durable and can take more abuse..

But if you want to keep the tens of thousands of M96/7 engines that still have Lokasil bores from scoring , the data, ( or Meta data) and a bit of redesign will be needed...

Don't worry, you will get over it I promise !!!! It may take 10 years but the nightmares and cold sweats will go away and you will be stronger/happier/more knowledgeable !!

 

Ya,,, just like that...lol

 

I disagree with a front mount air to oil cooler on a rear engine car.
Unless engines lubrication system was designed for that long a pipe run, ng. Pumping 5-50wt oil that far will cause lubrication losses/issues. Every foot of hose/pipe, every bend in pipe, is a restriction that cause pressure drop. It adds up fast. But it will still cool oil nicely.

Best to keep the pipe run as short as possible, with large enough id of hose and cooler.
IMHO, Key here is a very high cfm fan with proper shrouds on cooler. In our application, best to use a small air to oil cooler that is designed to be compact with big heat transfer capacity,, with the right amount of forced airflow.

While most of the time especially for radiator placement, a good airflow area or a ducted fresh air area is very important for good btu removal.
But here we are talking about a small oil to air cooler with turbulent flow/high pressure, that has huge differentials of temps. 230°oil - to ambient air of maybe 100°(?) when mounted in any under lid/under car/under rear bumper area. As long as its positioned to avoid recirculating the same air, it will cool extremely well is my experience with coolers with big cfm fans.

With added temp sensors in both lines its easy to see exactly how well its removing heat. And worst case scenario, these temp differentials will tell you if its in need of ducting or repositioning. My guesstimate is a good(small but well made/big cfm fan) air to oil cooler install will lower oil temps 25°-50°.

If a front mount air to oil cooler is needed/wanted then a different route is probably best. If trying to remove/negate the added heat on #6 cyl, install the oil cooler adapter plate with a short loop bypass on water and oil line.
Then use A separate electric oil pump, with supply and return lines on sump area would be best. Probably a low pressure system with bigger air to oil cooler would avoid aerating the oil in sump. This might be the best way, but more costly and more complicated

jmo

 

There are a few folks out there with an FSI build that have an oil cooler for a 3rd radiator. Maybe they can share some insight.

CTS developed one for their Boxster Race cars. It was $8,500 a number of years ago. I don't believe Chris developed one for the 996. He suggested that the cost may prohibit sales.

Other than a 3rd radiator and replacing 996 oil cooler with the 997S oil cooler, the only other oil cooling choice thats available on the market is the LN Cayman cooler that Charles developed into a 996 cooler woth all of the plumbing which resides where the muffler would sit.

I am keeping my fingers crossed that a "sausage" cooler is successfully developed to fit in the alley in front of the trans.

Certainly helps if the 996 owner runs plenty of fresh, high viscosity oil that is more resistent to heat to keep the lubrication qualities intact.

For those that want a picture of the oil cooler on the engine, here is one from 2 years ago when my indy dropped my engine for a refresh. Unfortunately, i didnt know about the 997S oil cooler being a perfect fit and providing 20% more cooling capacity at the time, or I would have used it. You can see where the cooler sits and why Skips comments are relevant.

 

Wow! Almost too much info to read. The seller didnt want to deal with an inspection so sold to someone mode local who didnt care about an inspection. It was a pretty good price, $17k 95k miles no accidents, lapis blue, but ugly wheels/custom inserts, no ims job. Search continues. Thinking about springing for a 4s if i can find out for $25 for the bumpers

 

Too much to read??? Not at all.....You don't realize that your thread just identified and laid out the possible solutions to THE most offending issue that plagues the 996 and 997.1 engines, that is just the "tip of the Ice-burg"....but sparks initiative..

Much much much more to drill down to a specific elegant implementation of the best solution, and to have it widely accepted by the community , commercially available and profitable/sustainable to the maker....

But thanks to your thread for sparking the interest !!

Sorry you deal fell through , but there are plenty more out there, just keep searching and you will get a good one !!!!