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Brilliant thread, thanks to all for the wealth of information. I'm kind of torn in that I love the 987.1 CS, but I've been taking my '83 911 to hpde for more than a decade, slower but relatively speaking bullet proof. You could almost make the case for adding performance to the dry sump air cooled beast over addressing 987.1 shortcomings. Almost. Did I mention I'm torn? I already have the 2qt deep sump and accusump, so I guess you know where I'm headed.
 

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Its really about protecting the #6 rod bearing from scarring due to oil starvation and/or oil distruction due to high temp affecting the oil boundry layer oil protection. Please read RAT/540 blog on 200 motor oils tested to distruction, the flat tappet model seems to mimic our #6 rod bearing oil starvation plight.

The Porsche Motorsports AOS for the 987.1 drops into the same spot as the OEM one. I have been told by GT who races his rebuilt 3.4 (now 4.0) M97 Vision motor hard, that the internals of the 987.1 Porsche Motorsports AOS is different than the 996 Motorsports version to help suck oil foam/vapor from the heads. Its also more than double the price and he has gone through 3 of them.

I am looking at a 997 GT3 oil/water heat exchanger, which is more than double the capasity of the M97 one. So, with an upgraded center CFS Race 997 GT3 radiator, my oil temperature should not go above 250. Using LN screw on filter adaptor, Charles Navarro suggests a race billet filter (Powerfilter #10881) with 45 micron size filtration holes, which gives more oil pressure due to less back pressure to #6 rod bearing during the final 15 minutes of the run.

Charles also suggests to use a more viscous oil, like a 10W-40 race oil for added boundry layer protection. Usually these type oils do not flow well when cold, so not good for the NW and other areas where the 10 qt sump does not get up to 220 degrees very often and have a limited 600 milage usage. Oh, how would we even know the oil temp without a gauge, or better yet a oil pressure on those long high g left hand corners at 6500 rpm's. Makes a good argument for a set of easy to read gauges mounted on top of the dash like the Sports Chrono wart. WRX makes a nice looking gauge holder and Autometer makes great looking 2 5/8 full sweep mechanical gauges.

Am I going over board, or is this just not wanting to face a $20k rebuild bill knowing I would opt for a 4.0 Vision motor, Nickies cylinder sleeves, beefier Carrillo rods and rods bolts, crank oil passageways opened up, better oil return passageways in the heads that were ported and polished to brethe above 7800 rpm.
 

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Discussion Starter #43 (Edited)
Bought a set of 996 swirl pots to go with my Mantis 2qt deep sump and a spare OEM AOS. After reading oodles of threads this seems like the best setup to prevent oil starvation/aeration. Motorsports AOS will follow next season or if I get flagged for blowing smoke at events. I'll be running 180tw tires w/o any real suspension mods (only rear sub brace) and our track doesn't have any high speed sweepers which are the worst for these engines.

The Mantis sump has lips built into the bottom of the pan to prevent sloshing and direct oil during hard cornering. The LN kit solves this with an upgraded baffle. While the LN kit includes straight return tubes Cayman's already have these so it's not an upgrade for most of us. The older part book shows the wrong tubes (as designed vs as built). The latest one has the same tubes as the LN kit. I'm assuming LN sells it this way to support all variations of Cayman's as the M96 engines may be different than M97 builds. FWIW the 911's at the time use the swirl pots, which makes you wonder if the straight return tubes were a cost savings on the Cayman.

Mantis's design is a simple solution to a complex problem and doesn't require running race oil like LN's does. Their pan design keeps oil at the pickup and doesn't rely on the baffle to counter sloshing. I think this is why you see so many race builds using their kit with 996 swirl pots.

The only solution I'd feel completely comfortable with is a hardened block and new rods. That combined with either sump kit and a Motorsports AOS is the only true solution to common failures. The aforementioned oil modifications won't prevent rod issues if you over rev or have aeration issues. That is probably out of reach for those like myself who are daily driving their weekend track car. Shifting at 6k and not pushing the car hard for the full session is my plan.

All of the threads I've read on failures with that setup felt it was aeration and not a lack of oil that caused them to throw a rod. It's happened to people with a deep sump kit and double accusump. If you've done those mods and you're pushing the car hard a lack of oil isn't the issue it's the air in the oil near the end of a session that's going to cause you to throw a rod.
 

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All good points. So, from my research these #6 bearing failures usually happen in the second half of the run, when the motor oil is extremely hot, oil pressure is down, and fast times are happening meaning high G forces. Combine all of these factors, point to oil distruction, heat causing viscosity to go down which affect the oil protection barrier. The idea is to improve oil pressure by reducing back pressure using a billet oil filter screen with either 60 micron or 45 micron filtration holes on a screw on base. Buy the best oil that resists high temperature oil breakdown from an unbiased non oil engineer RAT/540 rating. LN President Charles Navarro, who runs LN/Bilt/BRS and has direct relationship with Flat 6 Innovations, say that 10W-40 wt seems to be the right weight oil to withstand this last of the run oil breakdown.

The oil must also have anti foam characteristics allowing the oil in the heads flow onto the windage plate without impedance. mgarcia048 had a 996 swirl pots and Mantis 2 qt deep sump, running Redline race oil, but blew up in the second half of his run from a rod bearing #2 issue. My opinion is an oil safe kit by TTP would be a benefit here sucking the oil/foam from the right head out with a vacuum pump.

The addition of easy to read mechanical, 270 degree sweep, oil pressure and temperature guages would certainly help here, knowing when to back off and save the engine for another day.
 

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Discussion Starter #45 (Edited)
mgarcia048 had a 996 swirl pots and Mantis 2 qt deep sump, running Redline race oil, but blew up in the second half of his run from a rod bearning issue.
This is exactly why I think you need a hardened block and new rods if you're going to race a 987. No amount of oil modifications are going to prevent the weak rods from blowing your engine. You can work around the oil starvation and aeration issues but there's aspects of the engine you can't without significant changes. If you're a potential buyer jump to the 2009+ gen if you own one recognize the shortcomings and play it safe :)

I'm a new owner and still happy with my decision after all the research I've done post purchase. The car I bought from my uncle that spawned this thread with the factory upgrades MSRP'd for over $100k and I bought it for $35k (47,000km odometer). I've spent a few thousand preparing and I know I have to be more careful than my previous track car but it's still completely worth it!
 

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I think we are seeing this activity already, as one potiential customer on P9, simply could not find a 987.2 Cayman S with SC after many months of looking, He did say one was available but extremely high price. So, that's the options. Owners of 987.2 S, simply are not selling and they were a small pool to start.
 

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Discussion Starter #47 (Edited)
I would never sway someone from buying a gen1 as long as it's an M97. Yes you need some mods but it isn't nearly as bad as people make it out to be. M96 on the other hand...
 

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jonez- I have been debating what to do for the past few months about my track engine upgrades, while doing a house project, which is now done. So, here is a list of upgrades that I propose to my local race shop, with the idea to keep the engine oil cooler, have more oil pressure to the rod bearings, reduce foam/oil accumulation in the right head and improve mid range torque/power.

center radiator plus installation.
Vision oil/water heat exchanger adaptor.
GT3 996 oil/water heat exchanger.
install of exchanger.
TTP dual vacuum scavenge pump for right head with installation.
Cargraphic long tube race headers, EVOMS Bosch ECU upgrade, with install.
LN Screw on oil filter base for bullet race oil filter (Powerfilter 10881) with 45 micron filtration.

So, that pretty much takes care of my race budget for the year. A pretty sizable investment into the race protection aspect of my car's enjoyment.
 
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