[Apex1]

Trying to find grip in the rain with Hoosier A7 slicks using lower pressures of 24f and 26r. Outside temp was about 40 degrees F.

 

[arthurc604]

None of those sound like ideal Hoosier conditions!

 

[Apex1]

The latest weather report was for overcast with clearing later in the afternoon. So, I had my slicks on. Luckily it was not standing water, just NW heavy mist. The Wavetrac LSD really worked well here keeping the traction balanced from apex to corner exit and also keeping the car straight on braking.
Crazy, my heart rate was pretty high.

 

[arthurc604]

Glad to hear that you had a good weekend. Mine was quite interesting. Morning runs were soaking wet and was my first time trying to race the car under those conditions. It was a real struggle to keep the car from understeering badly, and the oversteer breakaway seemed really quite abrupt to me. My codriver thinks it's partially due to our set of old RE-71R. I wasn't losing the car in a OMG-I'm-going-to-crash way, but just an OMG-I'm-losing-so-much-time sort of way.

I got so lucky that my afternoon runs were pretty well fully dry, and my strongest competition was in drying-but-not-fully-dry conditions. Ended up finishing top PAX out of 90 competitors but I know I lucked out this time. "Mother Nature, take the wheel!"

I did experiment a bit with pressures. Ended up using 32/30 in the dry whereas at prior events I was the other way around at 32/34. I still have a bit of work to do in terms of cutting a little closer to the cones on a consistent basis.

My codriver will be joining me for our next autocross which is a 2-day event where our best times across 4 courses are summed.

 

[AX 987.1 Cayman]

Congratulations Arthur, any day you end up top PAX is a great day. Really like your videos, motivates me to replace my broken camera.
I sometimes miss the wet race days, but that maybe a result of this past weekend’s 90+ deg days at Thunderhill/Willows on the skid pad with the PCA AX group. It’s only going to get hotter for AX events in the next 4 months. My results were not as stellar as yours. Used the first 8 of 12 runs to play with damper settings over their full range. Someplace in that testing I ran through the RT-660’s sweet spot and never got it back. Fun anyway and learned a bunch about what compression/bump damper settings feel like from the drivers seat. I hope it helps me next weekend’s PCA events at the very bumpy Cow Palace parking lot.

 

[Walter]

I got so lucky that my afternoon runs were pretty well fully dry

Nice run. But what's with the car launching in front of you in the finish braking zone?

 

[arthurc604]

Nice run. But what's with the car launching in front of you in the finish braking zone?

Yeah that was clearly a mistake by the starter, or the driver misunderstood the starter. I worked that position the next heat and the safe launch window was quite small. I actually didn't even notice it until I looked at my footage at home.

 

[arthurc604]

Congratulations Arthur, any day you end up top PAX is a great day. Really like your videos, motivates me to replace my broken camera.
I sometimes miss the wet race days, but that maybe a result of this past weekend’s 90+ deg days at Thunderhill/Willows on the skid pad with the PCA AX group. It’s only going to get hotter for AX events in the next 4 months. My results were not as stellar as yours. Used the first 8 of 12 runs to play with damper settings over their full range. Someplace in that testing I ran through the RT-660’s sweet spot and never got it back. Fun anyway and learned a bunch about what compression/bump damper settings feel like from the drivers seat. I hope it helps me next weekend’s PCA events at the very bumpy Cow Palace parking lot.

Thanks for all your comments! Oooof, our daily high temps are still around 55F. I had to Google "Cow Palace" and the origins of the name are hilarious. https://en.wikipedia.org/wiki/Cow_Palace#Behind_the_name

 

[PNW987.1CaymanS]

Well, I finally got to race the car again. The weather was finally nice (dry, mid 50s to mid 60s). I was starting to get a better feel for the car and push it harder. I was talking a good second to second and a half off of my times from run to run. On my final run of the morning session I had a suspected AOS failure.

At least I am hoping that is what happened. Under heavy braking before the final turn around, (at least that is what I was told). I was completely unaware of it until I started the car to move it from the grid, after gathering up my gear. Big clouds of white smoke.

It smoked again upon start up to drive back home. It drove completely normally, and was not smoking or making any strange noises as far as I could tell. It didn't seem to smoke on start up once I got the car home (about a 100 mile drive).

In the cars maintainance records, it shows that the AOS was done only 3 years, and just under 3,000 miles ago. This seems to be an awfully small number of miles for it to be failing already. I had seen talk of doing it every 3 years or 30,000 miles. The car seems to have not been driven much in the last few years before I purchased it. It is currently at 92,500 miles.

I will be taking the engine cover off for the first time since I bought the car. I will remove and inspect the AOS and buy a new one. Is this going to be a constant headache, or is there something that I can do to get longer life from this part?

FWIW, the pilot super sports felt great during the autocross. I started with the tire pressure a bit too high (32F-33R), and by reading the amount of rollover on the shoulders I ended up settling at 30F-31R. A guy with a base 987.1 Cayman next to me was running 30F-30R. He had the newer PS4 though.

I've got my next event in 4 weeks, so I should have plenty of time to get this issue fixed. Fingers crossed that my new tires show up by then.

 

[Apex1]

PNW- I washed down my AOS twice with blue/gray smoke after second run the first time and the fourth run the second. A guy came over to let me know my car was smoking, I thought I had broken a ring or something like that. Another came over and told me I had washed down the AOS so I got out of line and waited until all the runs were done and limped back to the parking lot. He told me to just let the car slowly burn the oil out of the cat and I should be OK after the drive home. This process twice really disturbed me. so on my next modification visit for suspension upgrades, I had Cantrell add a Porsche Motor Sports 987 AOS. After that upgrade, no more smoke. That AOS should have been changed after the 2006 season as Porsche had plenty of OEM AOS repairs. But they never did change to their improved version, they just added it to the repair inventory for $1800.00. Also the connect hoses are slightly different. The 996 Motor Sports AOS version is slightly different and needs some outside modifications to fit that space. The advantage is its about $800. The 987 version has better smoke filtration though.
For you with an OEM sump, just keep a OEM AOS and the cable snap ring plyers in a plastic bag for an on the spot repair. Hopefully its not raining as the engine cover needs to be removed.

 

[PNW987.1CaymanS]

I will probably stick with an OEM AOS this time around. I plan on upgrading the sump next year. If it fails a second time, I will probably opt for the much pricier version. I have a few maintenance items that I would like to get done before any expensive mods.

Thanks for the info, I will update once I have the engine cover off and the part removed.

 

[arthurc604]

That does seem like really short lifespan if it's the AOS. Do the records show that a genuine Porsche AOS was used? I'd suggest that you can start by popping off the hoses that go from AOS to intake at the intake end just to see how much oil there is inside. When I bought my car at 40k miles / 13 years old my PPI shop suggested that I proactively replace the AOS. Now that I've done it myself (very slowly) I could probably do it again within an hour. Mine did have a noticeable amount of oil but I had no symptoms at all. Another thing is that I try to keep my oil level at 3/5 bars on cold start.

I had a really good last weekend at my club's 2-day special event of the year where our best time from 4 courses are summed up. My codriver (creator of Solostorm) and I each have different strengths so we work really well to help each other find pace. First day I was somewhat behind the club's president (DSP RX-8) who was top PAX but on fun runs we found a huge amount of time by properly attacking the slaloms. That newfound pace was enough to bring me 0.1s on PAX time ahead of him on a total of 150s. Unfortunately on day 2 we both got screwed over because the other run group got dry runs in one of the courses while we had to do ours in the damp.

It really stings to lose due to weather but that's racing. Very positive though to find some new pace! We also had some pretty strong CSP drivers come up from PNW region and we were right on pace with them. Now thinking about attending Packwood National Tour in July... I know for sure I will be a mile off from top PAX there but would be interesting to find out how far.

Here's our fun run. With a street start + passenger + random attack by a course map I was still 0.1s faster than my best dirty raw time during the competition.

 

[PNW987.1CaymanS]

Thanks for the reply Arthur. I will have to look into running the oil at that particular level. Is there any concern that being at a slightly lower level could increase the chances of oil starvation? I am hoping to add a baffled increased capacity oil pan in the near future. Possibly on the next oil change.

Do you have an idea how much oil might need to be removed to lower from 5 of 5 bars, to 3 of 5 bars. I was thinking that I could possibly drain a bit out to get to that middle level. The dealership did an oil change before I got the car. I wish I knew what kind of oil it was. I've heard good things about Driven DT40 oil 5w30.

What do you run, and what amount do you add to get to 3 of 5 bars? I'm not sure what AOS was installed. The invoice didn't have any info on that other than the part was $147, labor another $312. This was in May of 2019. I guess I will know more once I get the engine cover off.

It will be interesting to see what is going on under there. I know that the car is supposed to have an aftermarket intake plenum, but I don't know which one. I will take a look at the air filter, as I have a replacement waiting. Is there anything else that I should be checking or inspecting while I have the engine cover off?

Thanks for sharing the racing footage. I am wanting to get a camera/race telemetry setup in the future. What is the one that you use?

Is Packwood open for anyone to enter? I have been there a few times, but that was 10+ years ago. I wouldn't mind checking it out. I know that it is SCCA, with some different class allowances. Maybe you could help me figure that out if I am able to go.

 

[Apex1]

PNW- You can sign up for SCCA and their Bremerton schedule. Porsche NW also uses the Bremerton race park. Sign up for both as they each have weekend events at Packwood. You will be coached up as much as you want. The guys at SCCA Bremerton will classify your car. The issue will be your modified induction system which will put you into a highly modified class in both SCCA and PCA. It only adds about 3-5 hp but disqualifies you from the stock classes.
LN makes a very good deep sump system. They also sell a protection skid plate and a screw on filter system, which I use. I'm also using their 10 qt deep sump and running the oil level at 3/8 full, while checking it every morning before startup.
If you intend to do DE's, your induction system will be useful at the top end of the the rev limits. Not so much for autocross. The deep sump with a windage plate will be very useful for DE's helping keep the oil in the sump rather than climbing the sump walls in long high G corners. Guy's that DE their cars also use modified LCA's to improve their camber, coilovers, much harder engine mounts and LSD's which is not allowed in stock SCCA or PCA classes. So, its important for you to join these two orginizations as soon as possible to hear directly from their rules experts what works and what does not. I know that PCA is trying to work with SCCA to standardize their rating system. But each year classes change. So sign up.

 

[AX 987.1 Cayman]

I added a LN Engineering 2 quart deep sump with baffle plate, gives peace of mind on running low on oil. The engine rebuilder I used adamant to never run the oil over the 4th of 5 bars. Only use the first start of the day, if on level ground, to judge if oil should be added and only half a quart when at 2 of 5 bars. If you do add a deep sump it is highly recommended to add the skid plate. With that extra inch the engine bottom is now the lowest thing in the center of the car. High Centering on a speed bump could be really bad. The center rear under car plastic sheet will also have to get trimmed back and inch of two for the skid plate to fit.
After the rebuild I have been using Driven GP-1 oil with very good performance, until the AOS fails. Went heavier to 10-40 because of the 100+F AX days we get down here in the Central Valley and the Cayman only see below 40F when parked for the winter.

This is also odd, I also had my AOS go bad at an AX event 2 weeks ago. I was leaving the car idle between runs and there was a break down on course that took 10 minutes to get off. After that ~15 minutes of idling as soon as I started to move I ingulfed the paddock in a cloud of smoke. Kind of embarrassing. Second time in 4 years for an AOS failure. Got the Cayman home and pulled the AOS off, about 90 minutes with the biggest trouble the hose clamp on the bottom to return oil to case. Then carefully pealed the top valve apart and found a hole in the diaphragm (photo). Ordered a new AOS and then searched the web for how to test the AOS, testers are expensive. That's when I got the idea to make my own. Ordered an oil cap for $15, found a inches of water vacuum gauge at 2.5" Vacuum Gauge 0 to -30"WC / 0 to -2"Hg, Back Mount (prmfiltration.com) for $29 and a 1/4" NPT tap from Ace Hardware and built one (photos). It is such a low vacuum that a change in weather will change static gauge reading. So, I use a differential pressure of what the gauge reads before starting the Cayman and after idling for a minute. I can't find a written Porsche spec for the Vacuum, but the YouTuber's say around 5" is good, over 10" is bad.
Looked at the $1900 Motorsports AOS, 987-107-926-00-OEM, but could not find out if it is not already on the Cayman does it still required the modification of the air pump and brackets. The DIY web installations look like they are using the 996 Motorsport AOS. Does anyone know if the "dent" in the side of the 987 Motorsports AOS eliminates these bracket modifications? The standard OEM replacement is $100, at that price I could replace the AOS every year for the next 18 and still be ahead money.

On a happier note, was 4th in raw times, top of my class, up until the AOS went. Looking forward to the next event. Also hoping for no failures.

 

[Apex1]

I have the 987.1 Porsche Motorsports AOS and the top looks completely different than the OEM AOS. Just open your motor cover and you can tell if you have an old OEM AOS or look at pictures of others engines. Yes the dent in the side of the AOS allows it to fit without modification. I also read that this AOS is better at filtering smoke as well as oil than the 996 version of the MotorSports AOS. Not that the M97 needs the smoke reduction as it can burn the smoke without it attaching to the intake valves like the 9A1 engines due to the port injection fuel. Yes, if you have the tools and an OEM AOS tucked away in your car, you certainly will be money ahead if you only need 1 blue smoke event a year. But the hassle factor is real, especially if you are doing a DE and get a flag for oiling the track due to the smoke.

 

[AX 987.1 Cayman]

Yes, if you have the tools and an OEM AOS tucked away in your car, you certainly will be money ahead if you only need 1 blue smoke event a year. But the hassle factor is real, especially if you are doing a DE and get a flag for oiling the track due to the smoke.

Thank you for the confirmation that it will fit. Looks like the cross hose to the driver's side valve cover and the vacuum hose to the intake manifold are also required.

Good point, next DE day I will have a new AOS and tools to change in the frunk.

 

[PNW987.1CaymanS]

I'm thinking of getting the new AOS from FCP euro. It is a bit more expensive than some other sources have it for($125 for a genuine Porsche one), but their lifetime warranty will cover replacements if it is a part that fails every few years. I'm hoping that the one that I take out is the same part. Then I can send it back as a warranty return in a year or so, then have a spare.

I imagine that you guys wouldn't suggest the cheaper non-OEM version. For the headache of the install, I would rather have something that lasts longer vs a cheaper part that may fail sooner.

I will remove a bit of oil to get to the 3 or 4 out of 5 bars cold reading. I saw that someone in the comments for the part on FCP euro suggested replacing a certain hose going to the AOS at the same time. Looks like a $20 part. Have you guys heard anything about that?

Funny that it was a Porsche dealer that filled the oil to 5 of 5. I guess they must not be aware of any issues that might cause.

 

[red_stapler]

Is there anything else that I should be checking or inspecting while I have the engine cover off?

Check the level of the power steering fluid, and consider running a longer overflow hose to discharge on the ground or a catch can instead of onto the top of the engine.

 

[arthurc604]

Do you have an idea how much oil might need to be removed to lower from 5 of 5 bars, to 3 of 5 bars. I was thinking that I could possibly drain a bit out to get to that middle level. The dealership did an oil change before I got the car. I wish I knew what kind of oil it was. I've heard good things about Driven DT40 oil 5w30.

I'd suggest draining 500-750 mL and then top back up if needed. I am running DT40 and following some of the bore scoring prevention practices such as the ones mentioned here:

I'm going to guess the dealer would just use Mobil 1 0W40.

Thanks for sharing the racing footage. I am wanting to get a camera/race telemetry setup in the future. What is the one that you use?

I am using SoloStorm SoloStorm Autocross Data Logger for Android - Petrel Data Systems It's quite expensive for being an Android app but when compared to travel and consumable costs for the serious autocrosser the price is insignificant. It's the premier tool used by lots and lots of the top SCCA autocross competitors. While I've found it can be beneficial as a single driver, it's an excellent tool when you have a codriver to compare against and use to refine your run.

In addition I'm use a GoPro Hero 4 and a Qstarz BT-Q818XT GPS receiver. SoloStorm coordinates the data from both of those, including starting the video recording once staged and downloading/rendering the video you see. It's all very slick.

Is Packwood open for anyone to enter? I have been there a few times, but that was 10+ years ago. I wouldn't mind checking it out. I know that it is SCCA, with some different class allowances. Maybe you could help me figure that out if I am able to go.

Yes. If you aren't already an SCCA member you can buy a $15 weekend membership at registration.