Oil system mods for Track
 

Our beloved little cars seem to have reliability problems when it comes to track driving. I have had my share of this "problem" when my 3.6 engine had a piston size while driving on slicks last summer. It had a deep sump and 160° thermostat and center radiator as it is an S model.

Some say the heat of the oil is the root of the problem. I have no doubt that this is a part of it. Other say it is the R-compound tiers, Still others say that they register swinging oil pressure on all kind of tiers. I am sure high grip tiers and aggressive driving style have something to do with it, but it is more complicated then that.

My research on the web so far has led me to the following conclusion: None off the solutions that have been on the market so far seam to make the oil system 100% reliable and track worthy even though they help. I am thinking of deep sump, Accusump, low temp thermostat, X-50 baffles. or other oil baffle system, The problem seams to be that the oil pickup tube in the sump sucks air or aerated oil leading to fall in oil pressure, with catastrophic results. But it might not start there. The two heads have scavenge pumps located in opposite ends, in the back of the right head and in the front of the left head. I assume our cars develop the highest G-forces while breaking. When we brake for a long left turn, or while turning left in long turns, a good deal of the hot oil, which is thinner than water, flows to the front of the right hand head. In the front of the head it is out of reach of the scavenge pump located at the back. This in turn leads to oil starvation in the sump as it is not getting new supply of oil. I believe this is the root of the problem.

Porsche used tandem oil scavenge pumps that suck oil out of both ends of the heads in early X-50 models and in some race cars I believe. This solution is costly for Porsche pumps, if you are able to get those. LN engineering has a version for $2000 per head. This might or might not be the final solution if used together with some kind of deep sump / improved baffling in the sump.

It seems that the only bulletproof solution would be some kind of dry sump aftermarket system. The only problem is that there is no readymade dry sump system for our cars, Some have tried to make their own but it is not a simple task and there are also reports of engines failing while dry sump is being tried out/developed. Some have had success but I have not been able to find any information on their systems or how they are made.

I plan on doing all the bandage moods on my next engine. Accusump and horizontally baffled deep sump. 160° thermostat and the bigger oil cooler from 997 3.8 L engine. I hope it will squeeze under 996 intake runners, otherwise I will use 997 3.8 runners. I am also considering putting a pair of extra scavenge pumps on the heads to work together with the OM pumps in the same way that the very expensive tandem pumps do, but using electric oil pumps as substitute for the tandem pumps as a cheaper solution. The mechanical OM style tandem pumps cost at least $ 4000 for the pair. I also intend to install oil pressure gauge that I hope will help me monitor if all is working as it should, and hope that the engine will hold up to its duty next time around.

I always wondered what the x-51 engine from the 2004 anniversary 996 would be like in a boxster..

There is a guy on rennlist with an m96 dry sump thread, I will dig it up and add it here.

I'm on 160F thermostat and 2 quart baffled deep.sump, and have oil temp and oil gauges. The pressure dips get worse as the oil heats up, if you are doing it up from scratch maybe adding in an.oil cooler and with the engine out you might be able to.put it on the engine bay in the right hand scoop?

Thanks for the advice and information, hope some more of the "big track/race guys" will comment on this thread. Seems like many have lost an engine at the track.

It would be very interesting if you could "dig up" the dry sump thread on Rennlist. Like I said, I will be trying out the 997 water cooled oil cooler, it is about 20-25% larger then OM Boxster S cooler. The part number is 99710702500 an there is a picture below. It is 5" high with the Boxster S cooler measuring little over 4" . I believe it is possible to squeeze one under The Boxster 2.7 and S manifold, but you might have to bend the water overflow pin at the top a little. As I said, I intend to fit 996 manifold on my build.

If I still get dips in pressure with it, I sure will look at external oil/air cooler or a dry sump system. They are said to keep everything much cooler

https://dl.dropboxusercontent.com/u/...220_220217.jpg

https://dl.dropboxusercontent.com/u/...220_220157.jpg

Expensive/complicted solutions probably do not help much so here is a simple one. Like you I fitted a deep sump kit. It came with a horizontal baffle but the Instructions were wrong about where to fit it. I fitted it in the correct position and the Instructions were changed.
If your kit does not have a horizontal baffle - try one? If it did come with a spacer+horizontal baffle- where exactly did you fit it? Imho it should be above the spacer. The Instructions said below. Now they are "above".Makes more sense to have the much deeper insertion of the pickups.But if the vertical baffles leak....
Did you use the 997 pickups+extenders?
Did you use s/s vertical 'flaps' in the vertical baffles ? The plastic ones flop around and warp so do not seal well.
Investigate the heat exchanger delete plate + a dedicated oil cooler .Vertex sell one.
http://986forum.com/forums/boxster-racing-forum/65050-heat-exchanger-delete-oil-cooler-added.html

The 997 cooler is too tall to fit under the Boxster intake. The 997 intake is a couple inches higher than the ones used in the Boxster, and the "S" cooler is as tall as you can go without major difficulties with a Boxster intake.

Here is the M96 dry sump thread from rennlist:

Dry Sump Kit for M96 and M97 engines - Rennlist Discussion Forums

Gelbster, I had the plastic baffles with rubber doors, but all the extensions. But the jury is still out on what to use in the new build. Mantis seem to believe that the plastic/rubber seal better then the s/s X-51 type.

And JFP, I am sure you are right regarding the Boxster manifold and 997 oil cooler, but I intend to use the manifold from the 996. It is higher than the Boxster one, but lower than the 997 one.

Thanks for the link Steved0x, Much appreciated

Are you using the FVD pan & baffle, I think it's the best.

Are you using Driven racing oil ?

FVD here scroll down for lots of photos:
FVD Brombacher Online Shop - FVD20798801 - Oil pan, FVD Motorsport - Tuning → Engine → Oil_System

S cooler is about 4.25", 997 cooler is 4.75" - about 15 mm larger. enough room under the S manifold; you may have to trim the vent tube a bit.

Have you succeeded in doing this or quoting another source? I ask because JFP has been clear on this not fitting.

not yet. i have the 997 unit, and tonight i measured it, as well as opened my engine and measured the 986S unit, just to reconfirm the 15 mm height difference. the difference is certainly not 'a couple of inches' as jfp said. there is about 20 mm clearance over the 986S unit; again only potentially the need to trim the vent tube.

Perhaps it would be a good idea to modify the nipple before you fit it? A radiator shop might be able to attach a 90 degree bend in a convenient orientation?
Allow for about 1mm for the 4 seals. As you know they sit is annular grooves.

I said the intake was a couple inches taller...............

Just to clarify for those who missed a detail in Radium's post:
It is a combo mix+match deal :
use the 997(or 996??) intake+taller 997 heat X.
The 997 heat X + the original 986 intake would not have enough space.
Hence the combo deal.
Hope this helps.

man, there is a picture of a 997 cooler with a measuring tape on it in this thread. get out from behind your computer, go to your car and have a look. decide for yourself if it will fit.

The oil cooling is not the big issue on a track car. Oil supply to the bearings is, and no added capacity oil pan, X51 baffles, dual scavenge pumps, etc., or even Accusump will solve it. Those are "peace of mind" fixes for street cars, but don't really solve the basic problem of oil control in the engine. The only true way to keep a tracked M96 or M97 alive is a dry sump system. You might be able to get away with some of the band aids for a while on some tracks, but sooner or later you will lose the bearings.

But those failures could be prevented by replacing the bearings with a refresh. The issue is that unless you need an engine to last a long period of time, refreshing it would be more cost effective.

On the subject of the cooler. Wouldn't having a better cooler cancel the benefits of running thicker oil? Wouldn't running a lighter fluid provide better flow and protection to areas with smaller passages? I know the argument about tracked(daily drivers) cars need thicker oil, but that is considering that oil will rise much higher then stock, lowering its weight to a more suitable thickness.

Also more heat taken from the oil = more heat in the coolant = higher average engine temperate. No idea if that is more suitable then a high but acceptable oil temperature with lower coolant temperatures.

I have seen some approaches like with the LN or TuneRSMotorSports oil/water heat exchanger delete plate that split the oil cooling and the water cooling. Supposedly less load on the water cooling system, but you have to fit an external air to oil cooler to make up for the loss of the oil/water heat exchanger.

And it has to be fan-cooled so it is difficult to find space for all that bulk unless you place it in the trunk and ventilate it also.If you fit a minimalist exhaust - that creates some space as Mr.Stone has shown in some links.

I would say, thermostated sandwich plate with an E30 styled cooler located right under the oil filter attached to the brace plate would be easy to incorporate. We would have to test to see if the oil cooks at idle, but usually only at WOT that you start cooking oil.

Plenty of Mocal/Setrab units in every shape and size. Just depends where you make the space.The space is the problem.

Can anyone confirm a 997 oil cooler will fit under a 996 manifold?

It does indeed. Here is proof:
https://dl.dropboxusercontent.com/u/...224_233621.jpg

https://dl.dropboxusercontent.com/u/...224_233509.jpg

Here is a newer thread on the subject of oil starvation on Rennlist

Oil pressure in right sweepers - Page 2 - Rennlist Discussion Forums

As you can see from that thread, there IS a fix for the M96/M97 oiling problems, but it isn't easy or cheap. If you race an M96, no baffled pan, extra/bigger oil coolers, special oils, extra scavenge pumps, different AOS/catchcans or Accusump will fix the oiling problems. Chris of CTS has tried ALL of those and more even having a custom pan CNC cut, and none of them worked to any significant extent in endurance racing. I witnessed the carnage myself and saw most of his trials and tribulations. He went through a LOT of tests and had a bunch of engines lose bearings and whole engines in the process. He even put a clear oil pan on a Boxster and tilted the car every which way using a lift in ways it was not intended to see what was really going on in the engine. Another time he was at the track on an open track day intentionally over filling his car with oil (he got up to five extra quarts I believe - and no hydro-lock), and was still losing oil pressure in some situations according to his telemetry. I have never seen a guy so determined. Now he has a proven solution. It wouldn't be something I would do on a street car, but for a spec Boxster or endurance car I think it is a necessity. Chris did all the work, and I won't spill the beans as to his solution. Hopefully he will post it up in the thread you linked.

One thing I found really interesting is that the Boxster has a much worse problem with oiling than 911s due to the engine position. Apparently it does make a difference.

There is one possible thing to do which Chris hasn't tried that I suspect may help a bunch, and would be something that would be reasonable to do on a street or DE car. Perhaps I can convince him to give it a shot. I think all the parts needed are laying around.

This may help explain how they proved the lubrication deficiencies had been corrected - but how?
https://www.youtube.com/watch?v=fv53RbvgfGc

dry sump !

Suddenly , everything old ,is new again ! Hopefully the bean counters from the M96 days were taken to the wood shed. I right hander wiped out #5 on my M96 .Many thousands of dollars and many,many hours later ..................it is as reliable in a sweeper as a Miata, maybe.

Gee, I wonder why they made that fixture..? Not really. They obviously found the oiling issues on the M96/97 that those racing them are just finding now and realized that they had to do something about it. This is a much bigger problem than the IMS on tracked cars. It is a bit interesting that getting rid of the IMS on the newer engines also helped the oiling issue.

Why would an oil to coolant htxchr be helpful to any great degree on track? I would imagine the differential temperature would be quite useless in driving heat transfer from the oil when things get hot.

An oil to air htxchr is what would work to cool oil.....just like what has been used on ic engines for decades

One word: efficiency. Because liquid heat exchangers are more efficient at transferring heat than oil to air units, they can be much smaller. To use an oil to air unit that has the heat transfer capability of an S cooler, you would need one that would be more than three times the size of the oil to water unit, and then the question becomes where would you put it so it got enough air flow over it, keeping in mind that the oil pump in these engines preclude running it at the front of the car. People seem to forget that there is often a 30-40 degree temperature differential between the coolant (even when hot) and the oil, so there is plenty of temperature difference to accomplish cooling the oil.

Did you ever install that unit? I looked at my 2.7L motor in the garage. I have about 6.5" under the manifold. Was there more clearance in the 2003-04 engines than earlier models. Do the opening line up the same?

not installed yet - i am waiting until the next time i flush the coolant. the pic below shows the 986 S cooler in a 2000 3.2 S. the 3.2 and 2.7 are the same manifold regardless of year. the 997 oil cooler is 1/2" taller. i do not see any reason why it would not fit. there might be a bit of interference with the vent tube at the top, but it is easily bent to fit.

http://986forum.com/forums/uploads02...1489872082.jpg

Subscribed. Just put a down payment on a 2001 986S so want to catch up on current thinking. I had the TTP scavenge pump on my 987.1S along with accusump, X51 baffle and 996 Defoamers. It has held together for quite a while now (on the third owner). Expensive setup but cheaper than new engine.

Excellent food for thought as usual JFP...

^ What he said. Porsche obviously knew about air to oil coolers. They used them for decades on the air cooled cars. The thing is, it is quite easy to add an appropriately sized oil to coolant heat exchanger and then design the coolant system to work with the thermal load imposed by both oil and coolant. It works for the 911 Turbo as well and if anything would need lots of cooling, a turbo car would.

Oil pressure in right sweepers - Page 2 - Rennlist Discussion Forums

Nvm, need to read it in order next time.

Chris Cervelli of CTS has now a working dry sump system that he intends to put on the market. He has a new tread about it on Rennlist:

Boxster Dry Sump System - Rennlist Discussion Forums

???? Inquiring minds want to know :)