996 C2 AOS with R compounds

I have a 996 C2 - 99 that i will use for some club level racing. On my first day at the track i had huge amounts of smoke, especially after a long sweeping right hand turn. And the oil level went from max to min in only about 7-8 laps. I concluded that it must be the AOS that has given up on me. Removed the AOS yesterday but found that the diaphragm seemed ok. This makes me a little worried. Is the stock AOS that bad that it cant handle serious track work with R-compound tires? Are there any workarounds? I have seen that there is a motorsport version of the AOS, howerver it seems to fit only on models newer than -02. I am now considering repalcing the AOS and adding a catchtank, but if I lost 1 quart of oil during my 7-8 laps this is not an viable option either. /Peter

There are some on here that track and can probably give you some good ideas. It probably was the AOS that got overwhelmed with oil from the crankcase on a long sweeping right hand turn. The oil is forced to the drivers side where the crankcase breather hole is for the AOS. One recommendation is to get a deep sump oil pan with improved baffles. That will keep the oil from sloshing around and keep it under the pickup tube. I could be wrong, but I thought there was a Motorsport AOS for your car. Very expensive, but so is your hobby.

I already have the deep sump oil pan installed so thats not the issue Is there anyone that has the motorsport version of the AOS installed on a -99?

I would call these guys and ask...the ad says fits 99 C2 http://www.patrickmotorsports.com/pa...acing-version/ Or: http://www.5150motorsport.com/porsch...oil-separator/ An alternative: https://rennlist.com/forums/996-foru...separator.html

Just a quick note, when my AOS started to fail I would get smoke only on sweeping right hand turns. Carousel at Road America or Milwaukee Mile outside loop. It eventually gave way to full on smoke at idle. Two suggestions, get the motorsports AOS or someone hinted of a DIY oil catch can solution being developed by someone in the Boxster forum. The catch can is a band aide though. Maybe do both. Or just ask them to run in reverse from now on.

I've noticed the same symptoms from over filling the oil. Try only filling to the middle of the dipstick marks.

The motorsport AOS is not an option for the 3.4,s. that's not to say it has not been done, but it is not a easy or clean installation. It involves removing the engine and tapping the block for fittings using rubber hose and making brackets to mount the housing. Lots of race cars running the stock AOS with no problems. Replace your old one and go.

http://www.suncoastparts.com/product...=CarreraSSport Note: Professional installation required by a Porsche race shop (with experience with this upgrade), modifications may be necessary Also found this: https://rennlist.com/forums/996-foru...parator-3.html

Thanks for the input guys! I will replace the AOS even though it seemed perfectly fine upon visual inspection. I wil also install a catch tank on the hose going from the AOS to the inlet manifold just in case to prevent hydrolocking.

Sounds like you were overfilled from the start. You need to check with the dipstick after the car sits overnight and is cold. Leave the digital one alone. I have the deep pan as well and if I've over filled the oil it will smoke between sessions. Totally normal.

Adding to the above for reference: Was at the track this weekend. 80 degree day. Cold the morning of measured in the middle on the dipstick and 4 bars from bottom on the digital. Throughout the day following 20 minute lap sessions I had AOS Oil Smoke on the following start up (some 40 minutes after cool down lap) after each until 2pm. Didn't add any oil during or after. Day after measured just above the line on the dipstick or 2 bars from bottom on the digital.

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+1 I run a 99 with stock AOS and (knock wood) no worries. I was just running a track with very fast, banked right hander - and I was warned by the techs in my garage to keep oil level down a notch or two on those tracks...!!!