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Discussion Starter #1
Me and the wife (Cathy) have been autocrossing for two years now, in HS MINIs, and I've taken to writing up the experiences (see: First Autocross - North American Motoring, My 2013 Season - North American Motoring, An early start on 2014. - North American Motoring), its useful to be able to refer to these later. So far I managed to come second in the novice championship, second in this years HS championship, and 10th in the BMW Club's "Top Driver Shootout". I've come as high as the top 10% in PAX in this region which prides itself on having the most national champions of any region. We even made it to nationals this year, where I was pretty irrelevant, (though the car did get the 6th best time on one course on one day, not with me driving, so its pretty well sorted.) While we didn't buy the Caymann with autocross in mind, I was eager to try it and expecting it to be good fun.

So, yesterday I did the first autocross in the Cayman (Cathy couldn't make it). The Golden Gate region of the PCA was having their last event of the season (#9) in the usual place, on the runway at the old Alameda Air Base (see: http://goo.gl/maps/nUQth), you might recognise this from Mythbusters, its one of their favorite locations.There were lots of Porsches of course, but also quite a few miscellaneous cars, quite a few names I recognise from the local autocross scene. Obviously its quite popular to get invited to these events.

This may be even more crucial in future as currently it looks like there's nowhere down in this area to hold events. There was due to be an SCCA slush season this year, I'd expect to have done a couple of events already, but that's on hold due to scheduling problems with Oakland, and Marina not taking any new bookings for the year. The problem at Oakland is looking like the SCCA might lose its main site for next year. Marina is already under bureaucratic death sentence as the FAA finds autocross inconvenient. Candlestick is being redeveloped, and someone built a stadium on Santa Clara. Crows Landing is expensive and inconvenient. That accounts for all the active sites the local SCCA uses, so the outlook is grim.

At least the PCA has its venue at Alameda, because of local politics the PCA, and only the PCA has been able to use the site, though lots of other clubs would love to hold events there. So one of many good reasons to buy a Porsche (along with more luggage space) was that at least there would be somewhere to autocross next year. I heard that things are changing at Alameda as well, the VA is now in charge, the bureaucrats might not appreciate the autocrossers. Porsche were due to hold one of their World Roadshow events at Alameda a couple of weeks ago, but they suddenly moved the venue elsewhere, that didn't seem like a good sign.

For the event I finally had the alternative wheels ready. I'd ordered some custom wheels (from "Complete Custom Wheels") as none of the off the shelf options available were exactly the right size and offset. I was looking for the maximum allowed by SCCA Street class rules. Unfortunately the first set didn't actually clear the rear calipers, so I had to get replacements. CCW were great about getting the replacements, but it takes a while to custom make a wheel. I put Dunlop ZII tires on them (in 245/40-19 and 275/35-19). I went for the ZII rather than their supposedly better replacement ("ZII Star Spec") so I could get a good comparison of the Cayman vs our MINI (which has been running ZII). Or I would if we could ever find an SCCA event where we could run both for comparison.

With a new setup, I had to find the right tire pressures. I'd been doing my usual thing and running them on the street and looking at the tire temperature profiles. This showed that the ZII liked about 48 (front) and 42 (rear). During the event I monitored the tire temps and they looked pretty good, maybe slightly overinflated up front. With the on board TPMS sensor giving live readings of pressure, it was a little alarming to see the front hot pressures exceed the maximum tire pressure (as printed on the tire). I was surprised the fronts heated up so much, until I found that the front radiators exhaust their heat right onto the front tires. This may be a handy feature unless your front tires are overheating. I made arrangements to even out this heating on future runs (by moving the car periodically about 1/3rd of a circumference to present a different side to the heat). Its certainly something to take into account. After a few runs I let out a couple of PSI and the resultant temperature profiles are the best I've seen from a road car.

The wheels put me in the AX07 (650-700 points) class with 700 points (the PCA here uses a points system to sort cars), the wheels added quite a few points, the rest were for PDK, sport suspension and the limited slip differential (as part of PTV), on top of 505 points for being a 2015 Cayman S. I've also found out that if I didn't use the alternative wheels I can run in "Showroom Stock" class (where it'd be SS05), for that you have to run OEM wheels and OEM tire size, but could use alternate tires. I've been thinking Michelin Pilot Super Sports might make good replacement tires when he current street tires wear out, and they're also one of the go to tires for autocross. Though someone pointed out that Michelin Pilot Sport Cup 2 tires are also within the rules, PSC2 tires are Michelin's latest "streetable" competition tires, that might make a good SS05 setup.

I also managed to sort out the problems I'd had with the data "system". At our track day last month I'd found no where to mount the external GPS device which makes things work a whole lot better and I hadn't used the OBD device for engine data as it stuck out so it was in danger of being kicked and braking something. I found strapping the GPS to a cupholder worked (thats one use for them), and an ODB extension cable worked so I could tape the OBD device to the fuse box lid out of the way.

I had been planning on making a mount for the internal GoPro camera, but I never got around to that in time, so I used a suction mount on the back of the seat again. This was not a good mount, it was much too wobbly, and the video is unusable without much post processing to stabilize it. With one of the suction mounts in use, I only had one left to use as a cone cam, I put that on the right side. Its the right side I was having trouble with at the track day, I didn't know where it was. So its going to be useful to see how close I got to things.

Possibly because of the shortage of autocross venues currently, it was noted that this event gathered the largest turnout of the year. There were 132 pre-regs and quite a few drive up entries. The PCA's run group ordering and worker selection is different from any other I've run. At registration I was directed to sign up for work in either red or green, but not blue. It seems the sheet you sign up on determine your rungroup (either red, green, or blue, blue seems to be reserved for non Porsches). At the drivers meeting a dice is thrown (they have one with red, green and blue sides) to determine the order of the run groups. I was in green, which turned out to be work, rest and then run. There were also two sets of runs, you got to work, rest and run in the morning and then again in the afternoon.

For my assignment I signed up for timeslips, this may have been a mistake as my handwriting is terrible. Carlsen Porsche, a local dealer, sponsors the events, so there is a lot of Carlsen branding, including the timeslips. The timeslips also had spaces for car number, as well as cones and total time (after adding in the cones). I couldn't hear the commentary, so I mostly didn't fill in the cone counts. I tried to write the car numbers on the slips, which made the process more complicated, as no one else seemed to be doing that, I gave up and just wrote times in the afternoon. As fancy as the time slips are, they aren't self adhesive like the post-its which are usually used, which made them somewhat inconvenient. As I was doing the timeslips and making note of all the times, it was obvious that low 60s would be a good time, the very best times were 53s, but not many cars broke 60s. It was also obvious there was a wide range of talent and commitment among the drivers, with 70s and higher being not uncommon. The highest were over 100s (that's one hundred, not 1:00).

As the course was on the good bit of runway (the lighter coloured bit on the map), the course was long and thin, with just the extra bit going off to the right. It suffered suffered a lot of the same problems course at Crow's Landing suffers, being very long and thin, without much variation. To break up the monotony the designer put in a very tight figure 8 at the beginning of the course. He was going to put in a "cinnamon bun" two turn spiral but was persuaded by a rampaging mob to change his mind. Ironically, the course designer couldn't make it to see his creation, he had to work. I had my usual problem with a long course, I couldn't remember it all at once, so a lot of the time I was driving by sight, not to a plan.

Not that I tried to plan much, I really had no idea how the Cayman would behave to be able to plan a decent line through the course. My plan for the day was more to do with exploring the handling of the Cayman rather than being competitive. One thing I did want to try was stomping on the throttle and see what effect it had. Autocross is one place where you can do that sort of unwise thing safely. I was planning on letting the PDK change gear for me, one less thing to worry about, and in Sport+ mode it sounds like it uses a pretty optimal gear shift strategy. I notice that there were times I thought it might have changed down, but didn't. A change may have been inhibited by the g lockout, it won't change gear when you're pulling high g's, which is most of the time at autocross. One run I forgot to put the selector in D and left it in M as I usually do, then wondered why the engine bounced of the limiter, and quickly threw the stick into D.

My first run was either a triumph, or disaster depending on how you look at it. I did stomp on the throttle and the effect was interesting, but manageable, as hoped it would get the back end to swing around more. This lead to lots of cone carnage, then I got lost on the return leg of the course, I forgot the second slalom existed and more or less just drove over most of the cones. I got a 63.5, which was a lot faster than I thought I'd be able to do, and also a DNF. There's no record of the cone count.

The next two runs were a disappointing 66.2 and a 65.8, both DNFs. I was still not worrying about cone carnage, but I was trying to make it around all the elements which obviously slowed me down a lot, more than I was expecting. I know I didn't even manage to make it around all the elements on one of them I think it was the third run, when I approached one of the bus stops on the out leg too enthusiastically and wasn't going to make the gate, so I just plowed on through the adjacent cones. I did think I'd managed a time on the other run though.

On my second run I came around the sweeper at the far end of the course used too much gas, got sideways, corrected and was just about to drive forwards when the PSM killed the power and I came to what felt like a complete halt. I'd deliberately left the PSM on, I wasn't sure what to expect in the handling department, and I appreciated the idea of the helping hand. The same thing also happened on an afternoon run, I think I'm going to have to try it without PSM next time.

Between running and working again I checked the on site (not quite live) results, all three of my runs were shown as DNF, so I wasn't sure where the third DNF came from. But as I didn't actually have a scoring run, I thought I'd make at least one clean run. So for my first run in the afternoon I drove not much faster than I might on the street, it was a 71.7, but at least it was clean. I forgot to turn on the cameras for that run, so there's no evidence apart from the time.

For the final three runs I again went for it and got a 66.3, 64.4 which felt more like it and a 66.0. The results show the 64 was a DNF and the last one was +1 but the 66.3 was clean so that's now my best run. The onsite results show that this is good enough to be 6th out of the 7 runners in AX07. The top AX07 time was 60.7, but 2nd was 63.2, so 2nd might be in reach. Interestingly all four of the SS05 runners, all Cayman S's, got into the 63's, so SS05 might make interesting competition. I'm awaiting the official results to see how I stack up overall.

I now know I have a lot to learn about driving the Cayman, I definitely need to be a lot smoother (especially with the throttle). I've decided that I'll drive the Cayman in the coming year instead of the MINI. I had planned to test the two against each other and see how they compared and which I could do better in (with a suitable index to compare the performances), expecting the MINI to be the more competitive car. But now I think I'll spend a while getting used to the Cayman. At SCCA the Cayman is buried in its class (against 911 GT3, Lotus Elise and the fastest Corvettes), so this is more for fun than anything. The MINI has also been nobbled this year as the SCCA has inexplicably thrown the Fiesta ST into its class. I doubt I'd be able to win against the Fiestas, though it might be fun to try.

I have video: http://btwyx.com/Movies/AxPCANov14Al.mov


I don't have any pictures of me in action, but here's a scenic:




And a video capture. The sun was setting as we finished:

 

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My 2011 Boxster and I were also at the event running in class SS04 in the same run group. Interesting course. In the morning I had 2 dnfs and a 70 second run. In the afternoon I finally figured out how to make it correctly through the course. My fastest time was a 66.7 second run but unfortunately collected 1 or 2 cones in the process. My last run, which I believe to be clean, was my fastest at 66.9 seconds. I feel that my times were slower than normal and it took too long to learn the course but that is the way it is some days.
 

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looks like fun! i personally wouldn't have liked that configuration for the track seeing as you needed a lot of steering lock for the turns. I like to keep my hands at 9 and 3, but when the turns are that sharp its almost impossible to do so. Keep practicing! looked like you did well!
 

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I'm surprised you can run pressures that high. At our last event I was starting at 38 and getting a lot of sliding from the rear (more than normal). My normal pressures are about 32/33 front and 34/35 rear and that's good enough for 3-4th overall at our PCA events even though I'm running stock P-Zero's. With the higher pressures I was about 3s slower than where I should have been - just didn't have the rear grip to throw it around or get the power down.

Next year I'm going to be running about 29-30 with possibly a little more at the rear.
 

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Discussion Starter #5
The ZII seem to like a lot higher pressures than the PZeros. On track I was dropping the PZero's pressures to get the hot pressure down to where they like them around 34psi or so. If I were running PZero at autocross, I'd be running them at the standard (for 19" wheels) 29/30.

The ZII seemed quite happy at 46/42, which wasn't a surprise as the ones I'd been running this year on the old car like high pressures. (One set liked about 48/45, the other about 42/40.) Each tire model and size has pressures where they're happiest.
 

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Discussion Starter #6
Today we finally got an SCCA autocross event in the Cayman, the season opener “Boondoggle” at Marina airport. Usually there would have been the “slush” season in the autumn to practice before we got to the main championship seasons. However due to some issues there was no slush season, I managed to get to one PCA autocross (and Cathy didn’t), but that’s all we’ve managed. At least there is a championship season this year, all the autocross venues around here have an uncertain feature. We only learnt that Marina was going to be available for use at the end of January, so far there’s been no news of any events at Oakland which are usually the mainstay of the SCCA season.

California has been unseasonably warm recently, and Marina usually has the best weather in the winter (it can be downright cold in summer), so the weather was almost perfect, mid 70s and sunny (in fact a bit too sunny at times), but we got a little cloud cover later. The weather and the paucity of events recently made the event unusually popular, Marina usually gets 75-150 entrants, I heard there were over 200 for this one.

The Cayman fits into the Super Street class, but we entered in the indexed (X) class. The indexed class usually draws the best drivers in the region, that’s not us, but it also allows you to run a variety of cars and still score points towards the same championship. Originally we weren’t sure if we’d run the Cayman or our old HS MINI, and indexed would allow us to run for points with either. But after the PCA autocross I did last year, I decided to run just the Cayman this year, learning how to drive it, even if we weren’t going to be competitive.

I was keeping an eye on HS, if we hadn’t got the Cayman, we’d be battling the influx of Fiesta STs which had just been moved down to HS from GS, and were looking like almost insurmountable opposition for the MINIs. In HS, my opponent from last year, Brian in an older Ford Focus was battling six Fiestas. I was using Brian’s performance as a gauge of the competition as we were pretty evenly matched last year.

X was running in the last run group of the afternoon, so we weren’t expecting to run before about 4pm. We did however still have to be there for registration by noon. Registration usually closes at noon, but it was kept open longer today thanks to an accident on the freeway which was delaying a lot of people’s arrival. We managed to skirt the delay, but it looked like it was making a big mess of the traffic.

We would also usually work one of the earlier run groups in the afternoon, but we bribed some students to do the work assignment for us. The San Jose state FSAE team was there offering to do you work assignment for $20. We decided to take them up on the offer so we could go get some lunch. I’d signed up for car queuer, which is a job I’d never done before. The queuer enters the car number of the next car to run into the system. We’d had a short classroom session last month to learn how to do these system jobs.

Around 2pm we started to wonder if we’d actually get all our runs in before he sun set. As it was our run group started a little after 4pm, with a sunset due for 5:48. Looking at the times which had been run, I though a time of around 40 sec would be just about good enough to win, the HS times I saw were around 44sec, so I was hoping to better than that.

I ran first, as I prefer and I gave Cathy a lift. I was very hesitant, I was hardly on the throttle at all, though I did get a few bursts of hard throttle towards the end of the run. I got a 46.3, so I had some time to make up. Cathy went out next and I got a lift, she managed a 47.5. A quick look at the data showed she’d lost most of that time to me in the slalom which went diagonally up the middle of the course. I’d notice gears changed up for me at the beginning of slalom and only for Cathy at the end. I’d put the car in Sport+ auto mode, so we didn’t have to worry about gears. Sport+ auto is the most aggressive mode it’ll keep the lowest gear possible as long as possible, so we ran a lot of the course still in first gear.

For my second run I tried to be on the throttle more. I managed it, but I also had three moments where the back end was threatening to come around and spin. I caught them, but that slowed me down. I did manage a 44.9 which was a good improvement. I encouraged Cathy to use more throttle, but her next two runs were not significantly better than her first. Looking at the data, her second run was more aggressive through the slalom as I’d suggested, but then lost the gains later in the run, she said she had bobbles as well.

My third run was a little more aggressive, but also more controlled, I kept it going forward for the most part, so I came in with a 43.5. At least I’d managed to better Brian’s time in HS. My last run wasn’t good, I made several mistakes, so I sat on the third run time. For Cathy’s last run I encouraged her “More Throttle!”, she managed a much more aggressive slalom and came home with a 46.1. Still a little ways behind the pace, but an improvement at least.

Preliminary results are out: https://docs.google.com/a/nestlabs....C_voYYxphojY0e6SFSHtSxPBmM/edit#gid=248196478

They show 176 scoring runs. Mine was good enough for 11th of 13 in X, and 110th overall. The best time in X was 4.2s ahead of me on index. At my best in the MINI I probably could have come somewhere around 30th, about 2.5sec better with a 42.8. Cathy was 12th in X, 144th overall. In HS, Brian didn’t show very strongly, he was 6th of 7 with a 44.6, the best of the Fiestas was a 42.2, ouch. Also in X was Chris, who I’d spent my novice year battling (to eventually lose narrowly), he was still running the “Tangerine Scream” Focus ST, I only just managed to edge him on raw time, but came in about a second behind him on index.

I have video of course:

My best run: http://btwyx.com/Movies/AxFeb15MaBest.mov
Cathy’s best run: http://btwyx.com/Movies/AxFeb15MaCBest.mov


Here’s me:




and looking for my time:




Cathy:







Driving into the sunset:

 

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Discussion Starter #7
We’ve done several events since my last post, but for various reasons, I never got around to writing anything about them. Not least of the reasons was we sucked. We got a couple of the local events, and missed a few more and a couple were cancelled. There were also the national events, the tour and pro at Crow’s landing. Like I said, we sucked at all of them.


That was until we got back from our cruise, and finally got over the jet lag. At round 9 a few weeks ago, I finally started to feel comfortable driving the car. More to the point I was faster than Ed in his Fiesta ST. The powers that be, aka the Solo Events Board (SEB) has been messing with the car classing and putting some ridiculously fast cars in some classes. Cars that everyone previously in the class thinks should be classed in the group above. Of course people who own that ridiculously fast car are happy. All in all the SEB seems to be trying to speed up the classes, this makes the previous competitors unhappy.


Last year it was the Focus ST which dominated G Street (GS). This year the Fiesta ST was put in H Street (HS), when its obviously a GS car. We used to compete in HS with the MINI, so this was of interest to us until we got the Cayman and decided to concentrate on that. The Cayman is classed unfairly, so its never going to be a nationally competitive car, so we're in this just for fun. If we’d still been running the MINI, we’d be having troubles with the Fiestas and Ed in particular. If we could run faster than Ed, then its a good indication we could run faster than we did in the MINI. Up till now, I wasn’t sure we couldn’t have done better in the MINI.


This weekend we did the “Pro Solo” national even up in Packwood Washington. To recap, the Pro is a different format of autocross, my theory is that its designed to be a more exciting spectator sport, if the SCCA wanted to market it. It features head to head competition, two cars run at once on mirror image(ish) courses. The start is like a drag race, so some of the game is to do with coping with the start. You also run all your runs very quickly. You have two runs on either side in quick succession. You have one set of runs on Saturday morning, and another on Saturday afternoon. Then there’s another set on Sunday morning. That’s all you’re guaranteed to get, your time is your fastest of all your times on each side added together. So only two of your runs actually count, and you can afford to blow a few runs as long as you put in a good one on either side.
The start also deserves a bit of an explanation as its a large part of the game/excitement. As the car comes to the start line it breaks two light beams. These illuminate one light, then two lights, all three must be illuminated. If you’re too far forward the red light will come on, that’s invalid. Its to you advantage to be as far back as possible, but still illuminate all three lights. That’s called “staging”.


While you’re staging a counter is counting down, giving you 15 sec since the last car to stage yourself and get ready to run. When it counts down to zero, a buzzer sounds. One second later lights start counting down, two yellow and one green. Once it gets to green, you’re allowed to move. However, a third light beam in front of the staging lights measures your “reaction time”. You are not allowed to react to the green light in under half a second, or 0.500 or “five hundred” as its called. Numbers over 500 are good, numbers under 500 are a “red light” and your run doesn’t count. This is really a game, not a measure of reaction time as you’re usually reacting to something earlier in the sequence.


In the Cayman it works if you stage yourself and then put on the (electronic) hand brake. Then starting is meerly a matter of stomping on the accelerator as hard as possible. The car’s electronics then does everything else, the engine revs to 4500, and one of the clutches engages and you’re off. If you stomp quick enough at the second yellow light you end up with a reaction time of around 600. So the whole sequence takes about 1.1s to effect, but is relatively consistent. Most of the event I was trying to stomp on the gas harder and faster to bring the reaction times down into the 500’s. A low 600 is not bad, a high 500 about perfect. if you get into the low 500s you start to worry about red lighting instead. The commentary was mentioning some like a 502, or a 498 both close to perfect in very different ways. If anyone ever got a perfect 500 they’d win a free entry to a future Pro.


So we drove up to Washington starting on Tuesday evening, just getting out of the bay area traffic for Wednesday. On Wednesday we drove 8 hours to Portland and then the final three hours to Seattle on Thursday. There were visited with family, which was partly the excuse for this. On Friday we drove a couple of hours South round the back of Mount Rainier, a lot of it through the national park to end up in Packwood.


The site is an old Hampton Mills lumber mill, but is now disused. There are several others still working not too far away, so you can see they like to have a large asphalt pad to store their lumber on. It made for a very pretty setting, with pine trees right down to the end of the asphalt. Once the lumber has gone, it makes a pretty good autocross site. We also had use of the enormous cavernous barns on site. These held various of the other facilities like the grid, the paddock and impound. In normal Washington weather these are probably realy useful for keeping the rain off. In the freaky weather we had, it was useful for keeping the sun off. It got up to the mid 90’s both days, and was all sunny.


As this was in Washington, we got new tires for the event. The old Dunlop ZII tires we had been running were very nearly down to the wear bars. In California I might have got a few more events out of them, supposedly an almost bald tire is best, in the dry. In Washington, the law is such that the tire has to be above the wear bar (in CA it can be lower), and if it had rained an almost bald tire would have been pretty useless. The hot new tires is the Bridgestone RE-71R, so I got a set of those in the same sizes (245/40-19 and 285/35-19) as we had for the ZII. I didn’t bother getting them shaved, they’d get broken in and worn down a bit on the drive up. I also needed to find tire pressures for them, my experiments indicated that the recommended pressures were about right. In the end I ended up letting out 1psi of the front and their temperature profiles looked just about perfect.


On Friday we got some practice starts, checked in and teched and went for a course walk. We only walked the left side as it was too hot to stay out there for too long. With so many runs, six on each side to get it right, I’m less concerned about walking at the Pro events. We didn’t bother getting up early enough to walk the course again the next morning. This may have been a mistake. The course was slightly confusing, it looked like you went straight up to a hairpin at the end, with just a few pointer cones to go around, then come back the other side. In reality there was a cross over. After the first couple of pointers, you were supposed to deviate across the course, through a gate which didn’t look like a gate as it was side on to you. Then you go around the hairpin and back through the crossover gate and finish around a few more pointers.
My first runs weren’t too bad, 27s and 28s followed by 26s and 27s, but unfortunately my best was red lighted away. Crucially this was pretty similar times to Ed in his Fiesta. Now a Cayman might have an advantage over a Fiesta due to the start, so if you look at the last pro, I ended up 2 sec behind Ed, so even for a pro this was an improvement. What surprised me was how different the right side looked, so the right was my slower side.


Cathy didn’t go quite so well. She red light a 30ish sec run on the left then got lost on the right. She wasn’t seeing the cross over gate. After she got a decent 29 on the left, I tried to point out where the gate was, but in the brief time available didn’t manage it and she got lost again. In the calm atmosphere of impound, I pointed out which cones to look for, so when we walked the right course at lunch it was now obvious where to go and Cathy didn’t have any more trouble with that.
Then we baked in the sun while we worked our afternoon shift (we’d also worked first thing when the sun wasn’t so bad), and then it was time to run again. I got more 26s and a red light on the left. I’m not sure how much of an improvement that would have been. The really good news was I now a second in front of Ed. Cathy’s runs were not too eventful, she managed 29s on both sides after she managed to red light her first right side run. She took it easy to get a valid time and complete the course.
Before our runs I'd compared the data and worked out I was making up most of the two seconds by using more throttle out of the hairpin. So I encouraged Cathy to use more throttle there. The hairpin had a lot of possibilities, a popular one was a very wide approach leading to a late apex and a faster run on the “straight” down to the cross over. I was using a much tighter line, aiming almost straight for the hairpin, trail braking on the way in (to encourage rotation) and power over steering on the way out (to encourage rotation).


On Sunday morning were there even earlier, the weather even at eight in the morning was quite comfortable in just shirt sleeves, it was going to be hotter later. So we were looking forward to doing our runs and going home. We were not expecting to get into any of the challenge rounds and did not enter into the draw for the bonus round so we wouldn’t be expected to work. I had a quick look at the data from the afternoon runs and the difference I could see was I was now powering into the hairpin. Through the cross over gate you had one "kink cone” to negotiate, I took a slower line into that to allow more power on the way out getting to the hairpin. I was making up most of a second there. Cathy’s exit from the hairpin was now pretty comparable to mine.


My left side runs got faster, but I didn’t manage to better my best right side time from Saturday. I was deliberately sacrificing the kink cone after the cross over to get a better run to the hairpin. The most annoying thing was when I got a 499 red light, and then ran my fastest time by over 1 second. The 1ms too fast start meant that was wiped out. On the video you can see I’m not happy. By this time I’d got comfortable enough with the start so I could read the reaction time as I went by. I may have stopped worrying about driving, so went faster with the red light. I seem to have made up quite a bit of time by realizing the course wasn’t difficult. In several place I expected to go through a gate and then go around a pointer cone the hard way, but the pointer cone was pointing the easy way instead. I’d slow down unnecessarily in preparation for that. Once I realised the cones were pointing the other way I did’t need to slow. The course was actually quite simple, as always the skill is in driving it fast.


Cathy’s runs were pretty uneventful, except for red lighting her first left side run. She hesitated on the next left side run, so her reaction time was not too impressive but ended up knocking 0.7s off her time. On the right she had to good runs, about 1.3s faster than her Saturday time. Looking at the data, she was pretty much keeping up except around the kink cone, the hairpin and the run to the finish. She was keeping up powering into and out of the hairpin.
Ed didn’t better his Saturday times, so I ended up still a second ahead of him. If I hadn’t red lighted that one run, I would have been two seconds ahead, getting close on index. That second would also have put me in front of the Corvette in 4th place. All in all that 1ms red light is really annoying.


I compare my results to past runs against a bunch of local autocrossers, to get an idea of how I'm improving. The problem with this weekend is I only have Ed to compare to, so its not so reliable. On that basis, the official result is the best we've done in the Porsche, and actually not bad compare to our past performances. If I hadn't got the red light it would have been on of my top three ever best performance, so overall I'm pretty happy.


Video:


My best left (with red light): http://btwyx.com/Movies/AxProPac15BestRL.mov
My best right (sat) run: http://btwyx.com/Movies/AxProPack15BestR.mov


Cathy's best left: http://btwyx.com/Movies/AxProPac15CL.mov
Cathy's best right: http://btwyx.com/Movies/AxProPack15CR.mov









 

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On Sunday we did the PCA autocross event at Alameda, on the runway of the old Naval Air Station. That’s the same Alameda as the Mythbusters often use when they need a runway. This was their event #6, but the first one we’ve managed to get to. I did one PCA autocross last November, but this is the first one Cathy’s managed to get to as well. With the way they run events, we weren’t quite sure how this was going to work with the two of us.

Unlike the clubs we’re used to (SCCA and BMW), the PCA doesn’t run all cars of one class in the same run group. At PCA the drivers sign up for a random run group and cars from all classes are mixed up, and crucially if you’ve two drivers in one car, the two drivers must be in different run groups. We haven’t often run in different run groups like that. The run group order (which is determined randomly at the drivers meeting) mean that I worked the first run group, while Cathy had a break. Then Cathy ran while I waited for someone to relieve me, then I could go help her with her runs. Finally Cathy worked while I ran. Then the same pattern repeated in the afternoon.

Working first also meant I didn’t have time to set up the cameras and data system, so Cathy ran her first few runs without video or data. For later runs I was having problems with the data, it wasn’t triggering correctly. The course, as most course on runways, was long and thin. In this case the far side of the course came back past the start, the lap timer took to triggering on the start as it ran past it. I tried various things to get it to work, but it refused to work and eventually stopped triggering on the finish. This meant that it was impossible to compare data from run to run. Also as I was running after Cathy I wouldn't have anything to compare her runs to even when the data system was cooperating. In the afternoon, I could have compared her afternoon runs to my morning runs, but the misbehaving system meant I couldn’t do that either.

As it was Cathy started out with a 52s, which seemed like a good start and worked her way down to a 49s run. When it was time for me to run, I took a relaxed run to get a feel for the course, but the timing system played up, so I have no idea how fast the run was and I immediatly got a rerun. (It looks about 46s on the video.) On the rerun, I made a serious attempt at going fast and was very pleased to get a 44s, a whole 5 sec fast than Cathy’s time. My second run was an even better 43s, and the third run was a 42.8s, but I got a cone.

The course started before the concrete end of the runway, on some very ratty tarmac, so the start was designed so you didn’t have to accelerate hard and rip up the surface. There was about a 30 foot run before you got to a sharp corner. The timing lights started after the sharp corner, so it didn’t matter how fast you went on the lead in, you’d probably have to slow down for that first corner. To make life interesting the course then turned back sharply after the timing lights. So the lights were on the middle stroke of a very tight Z shaped bit of course. It was the cone at the apex of that first corner that I took out. I was trying to be more aggressive with the start and I overdid it obviously.

After the Z, the course was pretty simple, it went down one side of the runway, with only one cone out of place to make a kink. The rest could be done more or less at full speed. At then end was a sweeper to bring you back down to the other side which was again pretty simple with only one kink before you got to an optional slalom. Finally the course went off the end of the concrete onto the tarmac. The main issue was the end timing light was around a very sharp 180, not really big enough to be a sweeper.

For my last morning run, I managed to get lost. I lost sight of the gates toward the end of the out run, and drove straight through a gap in the cones. This was of course a DNF. I carried on straight into the far sweeper. That sweeper was begging to be run with some throttle to provoke a little oversteer. As I’d already blown the run, I tried it with a little more throttle than I had been using, it seemed to work. I was also trying to use even more throttle to come around the final sweeper into the finish. Cathy was working the station about where I first blew it, so I wondered if she’d called in the DNF. That would have been different, but as it was the next station called it in so Cathy didn’t have to.

After another session of work, I joined Cathy for her runs already in progress. Without good data, I could give her much in the way of pointers, except “you can go faster” and “more throttle”. Her runs got more or less steadily faster, ending with a 46. For my runs I was trying to better my time, while not collecting cones. I started off with 43s and 44s, slower than the morning. I was trying to drive more relaxed and “use the force”, I wasn’t sure that was working, but the last two runs were finally faster than the morning with a couple of 42s. The last run was only 0.07 faster than the previous one, so it took me a while to realise it was a better time. You can see my hesitation on the video.

I thought I did pretty good, so I was anxiously waiting for the results. They finally came out on Tuesday afternoon: Prelim. Results - Active heat (All), #6 - PCA-GGR AX06 08-30-2015 - Sun 08-30-2015

In class, I was 4th of 9 (Cathy 9th). Third place is only 0.4s in front, so I might have a shot at that. Second and first are 2s and 2s faster, so not much hope of getting much higher in class. The guy in first place came in 3rd overall (on index), stiff competition. Overall, I came 43rd and Cathy 100th of 119. I was 6.3 "seconds behind". My results are not bad, could do better. None of the usual people I run with were running, so its difficult to compare my performance to past performance.

I have video, without data due to the misbehaving timer.

My best run: http://btwyx.com/Movies/AxPCAAug15Best.mov (One camera had run out of space.)
Cathy's best: http://btwyx.com/Movies/AxPCAAug15CBest.mov

There was no one to take pictures of me, but here's Cathy coming around the final corner:







Or finishing, while a Boxster is just starting:


 

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Discussion Starter #10
Thanks.

We have no plans on doing any mods. There's very little we can do and stay within the SCCA street class rules, and currently the car is running fine for us, and the idea has very little WAF. About the only things we could do is change one bar, or change the shocks. We don't need a different bar, the balance is fine and the last time I tried that (on the precious car) it rattled too much, which doesn't help. Shocks would probably have more impact on ride than handling, a little more digressive would smooth out big bumps.
 
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