AOS Smoke Bombs, spins, a new fast lap at Roebling, and one that was a second faster
 

I had a good trip recently with Florida Crown PCA region at Roebling Road, I hadn't run with them for over a year due to work and family conflicts.

This weekend was interesting due to some unusual cars, and a Cayman (possibly more than one) that were smoking the track repeatedly with AOS smoke bombs.

If anybody every wanted to see what it looks like when you overwhelm the AOS, here you go:

Fast forward to 8:53 to see it along with a pretty spectacular spin that went on and on, I wish my phone wasn't blocking the view so much... The car that spun was some sort of 90's Honda station wagon and as the weekend went on, got faster and faster and passed most of the cars in my group (White intermediate solo)

https://youtu.be/es8UQcvkokg?t=8m53s
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Want more smoke bombs? Here are a couple more...

Go to 7:22 and also to 10:27

https://youtu.be/ENVc9f3a5PY

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I think I have some more the following day but that was too much video to sort though to post here...

One cool thing about the video above is that I mounted a camera facing backwards on my trailer hitch, and it got the rear shots but also some sound from the exhaust (Beluga Racing Exhaust). It is overdriving the mic on the camera pretty bad, but I blended in some of the audio so you could hear the downshifts, and some of the burbling and crackling on overrun.

Here is the rear view from my final Sunday session, where at least for the first part, the exhaust doesn't overdrive the mic. Also in the prior session (about 2 hours before) someone (GT3?) oiled down the track pretty good and it took forever to clear it. So you will see a lot of dust from the oil dry in the first laps.

https://youtu.be/psGRZsHwgzc

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One highlight of the weekend is I set a ton of laps that were all faster than my previous personal best, and one lap where I was chasing a GT4 and I was on track to beat my new PB by almost a full second and got jammed up right before the final corner by a Miata (or possibly the GT4 not realizing the Miata was going into the pits)

This was also my first experiment with using an external video with Harry's Lap Timer (as the Micro SD card in my phone apparently corrupted and I didn't get any phone video for the first two sessions)

https://youtu.be/fyDNw2ar--s

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One other experiment I was working, is a theory that a tire is at the limit when a change in direction does not product any additional force. For example if I am understeering my front tires are past the limit and turning the wheel more does nothing. I was testing this out in some corners by bumping the wheel to see if my front tires were near the limit. In some cases I was and nothing much happened, in other cases I was way below the limit and rocking the car like a barge. I don't know where I am going with this but it was an interesting experiment for me to try - testing with inputs to see if I am at the limit on my front tires or not. You will see me bumping the wheel in some of these videos, and that's why.

Also got to meet a fellow 986Forum member: swiftmotoring with a Red 986 with a silver hardtop which made me wish I had brought my silver hardtop...

http://986forum.com/forums/uploads02...1485905427.jpg

Dang it I thought I had a better picture that showed our cars together better...

Edit: you can see the white Honda in the background of the photo. This is the car that passed most of the white group...

Great write-up.

Thanks for posting.

What type of tires are you running on the car?

I recently picked up a set of Nitto NT-01 and some more wheels as part of a deal (it's a sickness) and so I was running them at this particular event and trying them out. Usually I run Hankook R-S3.

I should probably pick just one tire and stick with it, but what I have learned (and what works for me) is to mix it up, last time I drove on the R-S3 for half a day and then switched to a set of stickier tires for 3-4 sessions (Toyo R888) at another track called "The FIRM" in Keystone Heights FL, and I could really feel the extra grip and was a few seconds faster. During those sessions I got to build my confidence and feel in my body what it felt like to go faster. Next time I went back I stayed on the R-S3 and was able to match my times (what do you know, I didn't fly off the track at the first turn), and then the next time I went back 6 months later, still on the R-S3, I was able to take several seconds off. Maybe next time I will try the Nittos there and see if I can take more time off, and repeat the cycle.

It is all kind of a mental game with me. I know that I am not pushing to the limits of the tires but I had a couple of big spins and kind of lost my pace last year at Roebling when I was tinkering with setup and this is one way to help me build my confidence back up.

Here is a kind of auditory cheat sheet way to tell: If the tires are howling and squealing like the devil, I am on the R-S3... If the tires are not squealing like a monkey, I am on the Nittos. Either they don't squeal as much or I am so far below the limit that I could probably get better results by setting a pile of money on fire instead of spending/trading for more sticky tires...

One thing I will add to that, I have been running Carbotech XP8/10 pads in the front/back the last few events and they don't match up well with the R-S3, I get into ABS much more easily with them (could just be my technique though?) than I used to with the EBC Redstuff. With the Carbotechs matched with the Nittos, I can brake like the hand of God, modulating at will, and can pull the contact lenses out of the eyes of an unwary passenger.

Hey Steve,
Lucky you to live in a climate where you can track year round! Here in Montreal, everything is buttoned up til May.
I've done the upgraded baffle and generally run a couple of bars low on the oil gauge and haven't had too many problems. I haven't put in the deep sump yet. Did this completely solve the smoke bomb problem for you?

Steve,

I will be at Roebling March 3 and will study your videos.

What kind of seats to you have, and are you using a harness?

And how managing oil - stock AOS, and sump?

Thanks!

Gary

March 3rd, that looks like a private track day for a dealership? Should be awesome! Hopefully they have it setup so you can ride with some of the instructors. I always learn a lot in those types of ride alongs.

I have Recaro Profil XL seats floor mounted with Brey-Krause hardware with integrated sub bar, and 6 point Schroth Harnesses. I love it! It does slightly detract from daily drivability though, but since I don't use the car for DD it hasn't impacted me much.

AOS and oil details below.

I have had only 1 smoke bomb and that was my very first track day and it was caused by what I believe were the following 2 things:

1. I had accidentally overfilled my oil after an oil change that I did the day before. What happened was I did the oil change, then went and got gas. After I got gas, the low oil indicator was blinking. On our cars, after you get gas, it will show the oil level. In my case, the oil wasn't fully warmed up, and I believe some oil was still in the valve covers or other places in the engine and hadn't fully drained down to the sump, giving me a false low reading. I went home and it took another quart to get the oil level up to the full mark. After sitting overnight, it indicated 1 bar above full, which I think is the max the digital gauge shows. What I learned there was only to check the oil after the car has been sitting a while to give all the oil a chance to drain down to the sump.
2. The other factor I think was that I had just gone through turn 9 (right hander) at Roebling in 3rd gear at around 80 MPH and high RPMs, accelerating at the apex and by the time I was at track out I was at full throttle nearing redline, and I shifted to 4th. A fair amount of lateral force, and with the oil overfilled, combined with high RPM and then releasing the throttle for the upshift caused it. I have seen it on left turns as well, turn 1 at Sebring a Boxster behind me blew a smoke bomb. I was glad I was ahead of him :)

When I got home I dropped the canister oil filter and dumped the oil that was in there, and put a new filter and o-ring, and that lowered my oil down to around the middle.

Since then I have never had a smoke bomb over approximately 36 track days over the last 3 years with the following combinations:

Stock AOS with oil filled to half way between the high and low marks on the digital gauge combined with the following combinations:

• Stock oil pan and baffle
• Stock oil pan with EBS X-51 style baffle
• LN 2 QT Deep sump with windage tray and X-51 style baffle

I have never tried filling the oil to the top line with the above combinations on track. I (my opinion) feel these engines have so much oil that going down 2-3 bars from the line isn't going to hurt anything, especially now that I am carrying 2 extra quarts in my deep sump. Also I have heard from folks that added a catch can that if you fill right to the top line, it is going to go right down to the middle after a hard session on track due to slight oil ingestion by the AOS (as witnessed by oil in the catch can) and then stabilize anyway around the halfway mark. All just anecdotal evidence, if your motor blows and you have been running halfway between the bars that is not on me :)

I consider my AOS smoke bomb issues to be solved. I am in on the Stelan AOS project and may try that out when it becomes available.

I also don't go through corners at the top of the RPM range which I think helps with the AOS but I mostly do it because:

• In the next higher gear there is less torque and so there is more forgiveness if I am not smooth with the throttle.
• I (attempt to, and there are some exceptions) drive my corners so that I can go full throttle at the apex, if I am already at the top of the RPM range then I might have to shift right at track out or even before and I don't like that.
• It is easier on the car and doesn't seem to slow me down any :)

I have also bought a lower cost digital manometer and am going to be checking my stock AOS regularly. I will post a DIY thread soon, but here is a photo showing the approximate setup using a borrowed manometer from a friend that I used to compare with my lower cost one:

http://986forum.com/forums/uploads02...1485962106.jpg

I didn't get any video but a friend with a 2001 Boxster S tip had misfires coming out of that same corner this past event when his tip transmission had him in 3rd gear at high RPM coming through that same corner, stock pan and baffle with oil filled right to the top. He said he didn't see any smoke in the back but he may have been distracted by the flashing CEL. I used a code reader with him later to verify that it was misfires. I told him to shift the tip manually and go through that corner in 4th instead of 3rd next time and see what happens...

March 3 is for Harmony Motors, the Porsche dealer in Asheville. Apparently some of the local PCA guys will participate as instructors, I am really looking forward to it!

Thanks for the advice about rpm in turns, that makes sense. I just added the 997 TB and plenum so look forward to using the extra torque at the lower rpms.

Another seat question - my car is not a DD but since I live in the mountains of western North Carolina drive it whenever I can. I think the stock seats suck. I want a seat that holds in mountian curves, would work for occasional DE's, would be reasonably comfortable for a few hours drives (to tracks) and not a pain getting in and out driving around town. I dont have a shop nearby that stocks seats so cannot try them out.

Why the Profi vs Pole Position? The PP seems to be popular as it is basically same as the GT3 bucket, and looks like has a low bolster towards front of seat, facilitating getting in/out of the car.

Thanks!

A couple reasons, but before that I think the Profile XL and Pole Position are virtually the same at the base and width for seating (where the regular Profi is *tiny* and smaller than the Pole Position). The differ in the back and shoulders, with the Profi XL having wider wings and bigger holes for the shoulder belt.

For me, the Pole Position looks like the shoulder harness belts are too low for my shoulders and optimal angles, the harness would drop down from the Boxster roll bars, through the seat, and then up and over my shoulders. That would not be optimal as it would compress heavily down on my spine in the case of an accident.

Then I scored a deal on a Profi XL with mounting hardware from Mike Yi of this forum (although I think he sold his car and is no longer on here) and that led me to that seat.

I am 6'2", 36" waist and 34" inseam, and the Profi XL is a perfect match for me. AS long as I remember to take my wallet out of my back right pocket it is comfortable for long drives of 3-4 hours.

The seat belt receptacle was actually the tricky part and before I got that sorted it was a pain to drive when using the OEM seat belt because the receptacle was way down there. I have an extender now and that solved it for me.

The first time I drove on track with the seat I had just the OEM seat belt and it worked pretty well, the seat provides tons of lateral support and made a difference even with only the OEM seatbelt.

If you could score a seat of the GT3 "Alien eyes" seats that would be perfect, sets with sliders come up for around $3000 from time to time.

One of the biggest challenges and expenses of mounting racing seats is all the hardware, side brackets, adapters and sliders to mount it in the car. Add $300-$400 to the price of each seat if you want to do it right. That makes a pair of $3000 GT3 seats with sliders seem like a better bargain... and it is all OEM Porsche to boot.

Here is a very nice installation in a Boxster that I found, and I think it belongs to a member here, with what I think is a custom harness routing bar from Stable Energies to give the correct geometry for the shoulder belts.

http://i1199.photobucket.com/albums/...h/IMG_1039.jpg

This wouldn't work for me because my torso is too tall. Otherwise if I had found a set of PP I most likely would have gotten them vs the Profi XL.

There is a set of the GT3 on RL right now for $3500, if you need help shipping I can share all my tricks to help you do it for the minimum of cost :)

Euro Spec 996 GT3 seats with Sliders and other goodies - Rennlist Discussion Forums

Steve, thanks for the tip, I will look into that.

I have only been on the track a couple of times and can see how it is addictive. I am looking at tires, wheels (OZ Racing), seats, roll bar extension etc etc etc - its starting to get slippery around here!

And here is now a set of side mounts, sliders, and sub bars for Recaro Profi XL (and PP too I believe)

Brey-Krause seat mounts 997 to recaro spg xl - Rennlist Discussion Forums

I bought all my seat stuff used, if there is no immediate rush, you can wait until the deals come along and save significant $$$

Yes it is very addictive! And lots of fun! Yes very slippery....

Missed this, guess the title wasn't long enough.

Off work here and was looking for something to watch while enjoying my nasty cold flu/virus. Thanks for posting these vids Steve, always fascinating to see what our cars can do when driven by ppl who knows what they are doing.

More more more please... (and get rid of the stuff in your windshield (lap timer?). Its blocking 'our' view LOL

:cheers:

Thank you!

Will do (I love making videos), and I hate that stupid phone in the way too, I am trying to get it right at the top of the window beside the mirror but can't seem to get the mount to cooperate.

I also tried to mount it on the lower left of the windshield, but again couldn't get the mount to cooperate...

Maybe I will see if RAM makes adhesive windshield mounts, should be a smaller form factor than a suction cup (and since glass easy cleanup should I decided to remove), and see if I can rig something up...