08/08/06 BMW trackday at PIR. Yesterday the race brake pads arrived from Wilwood so I popped them in this morning. One great thing about Wilwood brakes is that the pad change is completely effortless. It took me 17 minutes to do both sides, complete with jacking up the car, removing wheels, changing pads, reinstalling wheels and retorquing the bolts. The right side rotor had some odd things on it, namely the brake dust 'smearing' from each slot.

This would explain the vibration I felt when using the brakes. Left side looked pefectly normal. It may or may not be coincidental that when the old pads 'vanished' earlier, the left side was significantly more worn than the right. Anyway, I didn't spend too much time pondering this - just popped the new pads in and went to the track. One thing I noticed immediately on the way is that the 'B' race pads have a lot more initial bite. When I got to the track I saw that the rotors had been wiped clean by the pads in just a few miles of driving. I was warned that if the pads are cold they will eat rotors so I hoped that this would not be the case when they are up to operating temperature. Thankfully the pads performed as designed. Once I got out on the track the brakes worked great, pulling consistent 1.0g stops, lap after lap. At the end of the day there was some wear but nothing out of the ordinary. Cool, finally I have a setup that works!

The usual assortment of cars was onhand, with the sole standout being a Lambo Gallardo, running in Novice group. The car stood out all the more by being driven VERY slowly, even by Novice standards. Now don't get me wrong, I'm all for going at your own pace and staying in the comfort zone. It's what I teach every student. What I question is bringing a car like this to your first trackday. Surely it's not the only car in the stable and it's just a lot more relaxing and productive to learn in a vehicle that's less flashy and intimidating. At that pace, a low-grade rental Kia would have done just as well and probably would have let the driver learn faster. But whatever, at least the guy was out at the track - more than can be said for 99% of Lamborghini owners. And, it's a pretty car to look at even if silver wouldn't be my personal color choice for it.

Overall the day went well, which was a welcome change from yesterday. My student progressed quickly and did not do anything crazy. The Mini worked and while experimenting with all kinds of different lines and approaches I set a couple quick laps, a 1:35.88 and 1:35.89. Not too bad for street tires and almost a half second faster than my previous best effort. Brakes make a difference!

For being only one hundredth of a second apart, the two laps are VERY different. One has chicane slow in/fast out, the other is the opposite (at cursor). Speeds through the esses and 10-11-12 are quite different too. Just goes to show, there's more than one way to do the same thing. The black trace has me going through 10 at 84 mph which is almost as fast as I had managed on R compounds. The car really felt at the limit there, squirming around and requiring constant correction to stay on the line so I think that's about all the tires can support through there. Speaking of tires, I'm tearing them up again. This is with only about 300 miles on this set:

I'll probably have them remounted before the next trackday (which is Friday). Sigh... Of course this was DarkHelmet's 9th trackday in less than 5 months and 5300 miles. I guess that's what it means when a car is my 'daily driver' :)

08/08/11 The first of a two-day Porsche Club national event at PIR. Of course my 'luck' with vehicles continues. First, I noticed that the Mini's windshield is cracked. Great, gotta deal with that now and the $500 deductible (since I can probably get the windshield done for around $350 if I don't go to the dealer, basically means just another thing I have to pay for right now). But whatever. For this event, the club decided they wanted all the instructors there at 6 am despite the fact that first car out is not until 9. Usually I show up at 8. But I did show up on time today which proved to be 'fortunate'. After tech inspection, I was checking the torque on the wheel bolts and one of them just sheared off! At least I had a whole hour to run home, drill out and remove the bolt stub and replace all the bolts with a new set. I buy enough wheels from TireRack that I have a ton of wheel bolts laying around since a full set is included with each set of wheels. So that was more of a hassle than any real problem. Also, since I'm tearing up the tires I had the fronts remounted inside-out the day before so that I have two fresh outer edges to destroy.

Being a national PCA event, the attendance is overwhelmingly Porsche with just a handful of other cars mostly belonging to instructors. A gaggle of GT3s was onhand, for example, with a few other interesting machines as well.

The day itself went as usual. Instructed a couple of students. Tore up tires some more. Running 43 psi front and 35 psi rear seems to help the wear but it's still bad. I'll need yet another set soon. Brakes are holding up - finally. Lap times about the same as before. Just playing with lines, strategies and ways to minimize scrub. The morning session is the fastest, also as before, because the track is still cool. As it gets warmer in the afternoon the tires start to suffer and so do lap times. But all in all a pretty fun day. Tomorrow, more of the same.

08/12/06 (updated 8/13) The second of the two Porsche days, also the 11th trackday for DarkHelmet since it first showed up in my driveway some five months and 5500 miles ago (hmm....). It took the Elise a full year to see about the same amount of use. I'm too tired at the moment to contemplate the meaning of this, it just is. Amusing, perhaps.

Overall, a very fun day. Bumped the pressure in the fronts by another psi to 44 cold and they survived three 25-minute sessions without incurring any terminal wear. Brakes worked well once more - with race pads the Wilwood kit is definitely the ticket (would stock rotors with race pads work as well? don't know, probably won't find out). Lap times followed the familiar pattern with the first session being the fastest in the low 1:36 range and subsequent ones getting slower as the track and the tires heated up.

My student, a friend of Larry's, made excellent progress which is always gratifying. The highlight of the day however was driving an Exige for a session (thanks, Scott!). It was really fun to play with a Lotus again and although I didn't push it very hard (not my car and owner's son was in the passenger seat), it was still highly entertaining. I didn't take any pictures or video but I did get a lot of GPS data. The main difference between Exige and Mini is in feel. As one woud expect, they are worlds apart, with the Lotus being very tactile and direct while the Mini is comparatively softer and remote (emphasis on COMPARATIVELY, since DarkHelmet is a very fun device in its own right). Exige FEELS a lot faster but the big surprise is that the performance of the cars is not all that different overall, the Lotus holding an edge that is much narrower than one would expect. I was only a second quicker in the Exige (see all the disclaimers above) at 1:35.3. The owner pushed the Lotus harder, with a best recorded lap in the 1:32 range which is nearly identical to Mini on R compounds.

In the plots above, the black trace is my best lap in the Mini (on V710s) of 1:32.9, before the brake upgrade, and the red trace is the Exige owner's best lap we recorded today of 1:32.8 (on 048s). Both cars are solo. The bottom trace is 'time slip' which indicates how far behind the Exige the Mini is lagging at any point on the track. It is interesting to see that the Lotus builds about a half second advantage by the end of the back straght, mostly by getting better drives out of the corners (an inherent advantage of RWD vs FWD) but loses all of it and then some through 10-11, making up some ground out of 12 again. What's really surprising is how closely the two cars are matched in acceleration and cornering. Wouldn't expect that a stock-engined Mini would stay with a 600 lb lighter Lotus, but it does.

There was another Exige in the Instructor group and I was running about even with him in both the Lotus and the Mini which provided a handy external reference and some further validation. I will need to spend some time going over the details of the data to see what makes these two very different cars work so similarly overall. When compared to the Elise datalogs in my archives, the Exige is slower on top end (understandably due to aerodynamics and power delivery that lacks some of on-the-cam sizzle of the 'Lis) but is much more planted through high speed turns. Just goes to show that things are not always as they seem and there is much to be learned still :)

10/18/06 Since it rained today and the planned dp1 track debut didn't hapen, Dark Helmet got to go. Which was actually fortunate - as it turned out I needed a forgiving car today because there would be much to forgive. The root of the problem is that I'd only had 4 hours uneasy sleep, trying to get the dp1 ready. Get it ready I did but as I was about to load the trailer David called from the track and said it was raining over there. So I left the dp1 at the shop and took the MINI instead. I had signed up to instruct for the day and my student is driving an M Roadster. With bald rear tires. Not the most forgiving car on a wet track, something I should have kept in mind when I was told that the procedure is for the instructor to drive the student's car the first couple laps to show the student the track and the line. First lap, exiting the chicane there is a transition from concrete to asphalt (the latter being much more slippery) and the back end steps out. This should not have surprised me. I had spun the M Coupe in this very spot a whle back (David did same in his once). But surprise me it did, precipitating a nice spin. No big deal, both feet in, even kept the engine running. But needless to say this is not what you want to show a novice student on the third corner of the first lap. He was admirably nonchalant about it - the comment was 'wow, that's easy to do'. Uhm, yeah. So I used it as a teaching opportunity to illustrate the consequences of failure to anticipate what the car is going to do. Bottom line is, on the track you have to plan and have ready contingencies. If you're forced to react instead of plan it becomes a game of chance and the odds are not favorable. My student later reinforced the lesson with his own spin but I think it was a positive lesson overall. He improved throughout the day and when it stopped raining in the afternoon he got to see how much fun a dry track can be. So there is a positive side to everything, with the right attitude. Keeping the car intact definitely helps (not everyone did, sadly, but again it at least served as a lesson to others and nobody got hurt).

After the track dried up I had a couple fun sessions. I had left street pads on, not anticipating running the MINI in the dry so if I kept going the car would see too much wear. Plus I was still zombified from the near-allnighter so I called it a day early. It was still fun. The couple sessions I did run I left the camearas and the GPS off and just enjoyed driving quickly. Not worrying about lap times, experimenting with lines or learning anything. I was probably not very fast but I was entertained and that's what matters. The car forgave whatever mistakes I made and willingly played along on occasions when I did manage to get it together. Very cool. Sometimes it's good to get back to the basics.

10/27/06 Likely the final track outing for the year, a Porsche club event. Mostly to share a trackday with an out-of-town friend. Also signed up to instruct. Thought about bringing the dp1 out but after going over the car realized it would need some maintenance and I just didn't feel up to it after the big push over the last couple of weeks. So we just took DarkHelmet. Forecast was good but the morning started pretty miserable - dense fog, cold and damp track. The fog was bad enough that you couldn't see turn 12 from the grandstands. While waiting for it to lift we did a track walk in small groups, each with an instructor explaining the track and its tricks (which are many, actually). My group consisted of just my friend and a couple other people. I ended up talking A LOT. It's a two-mile walk and there are many things to point out. The feedback was very positive though, so seems it was worthwhile. Around 11 the fog finally started to lift and we got underway, combining two of the sessions and skipping lunch to make up for lost tracktime. By noon it was totally clear and sunny and the rest of the day was perfect weather-wise. Cool.

What the combined sessions meant to me is that I was instructing in Novice and Intermediate and then driving in Instructor/Advanced. So the helmet never came off for over an hour and a half and I was always in a car. Eventually I just decided to skip some of my own sessions as I wasn't planning on running a 6-hour enduro. Overall, a great day. My friend had a lot of fun and did really well. She had run a few trackdays back home in her Elise but this was her first time at PIR and first time in a MINI. I rode along and instructed for a couple sessions then sent her out on her own. The last session she was running 1:40 laps, only 4 seconds off my own pace. Very nice. She also got a ride in a Honda-powered atom in the final session of the day.

My Novice student also did very well and was quite happy with the instruction. He was amazed (in his own words) to see what his 996 C4 could actually do when I drove a couple demo laps for him. He'll definitely be back next season. So all in all, a satisfying 13th trackday for DarkHelmet and an excellent finish to the season. Much to do over the winter. I'm ready.

UPDATE: got a link to some cool professional photos from the event:

Also, I would appreciate it if people reading this site would check out Friends Of PIR - an organization recently formed to defend PIR from some individuals with personal agendas who want to see the track shut down. It does not cost anything to join and you won't be spammed, but the more members we have (whether local or not) the more weight it carries with City Hall. Thanks!

12/07/06 Totally random. Was just walking out of the Home Depot and walking up to Dark Helmet, where I had parked it, and it looked like the car was hiding in the bushes. Kinda humorous. At least I thought so at the time - maybe you had to be there. So I just snapped a couple of pictures.

The track season is done and not much is happening, most notable being that Dark Helmet has just had its first service at 9,200 miles. That's quite a bit for me in such a short time. Trips to ThunderHill and Ashland will do it. On a somewhat less cheerful note, there was also a recent encounter with a curb. I have no excuse for it except total stupidity on my part (and that's all I'm going to say about that). But this did serve as a good lesson in designing for repairability and damage control. BMW has really done a great job with this car and to their credit, the prices on the little replaceable bits are very reasonable. The entire bottom part of the bumper is just $34 from the dealer. Some internal crush structures, etc. - another $50. Now granted I'm doing all the work myself (it's easy, especially with a lift) but still, this is a cheap AND valuable lesson. The timing is interesting, too, as I'm just digging into the production chassis design of the the dp1.... A positive side to everything. As long as i'm still around to look for it.

2/7/7 I'm always up for a fun experiment and to that end I finally got around to installing Airtabs on Dark Helmet. The car's shape is such that the back window and hatch always accumulate a hideous amount of dust and dirt. Today in particular it was looking in bad need of a carwash. This is something I'd like to change, hence the experiment.

So after administering said carwash I installed the Airtabs. The idea is to modify airflow in the car's wake by generating vortices at the trailing edge. The supposed benefits are reduced drag (and therefore reduced fuel consumption), improved stability and a cleaner hatch. I'm not really expecting a change that I would notice while driving and fuel economy is hard to judge because I get anything between 210 and 340 miles to a tank depending on conditions. However the dirt on the hatch is easy to see so that will be the gauge, at least to start with.

Mounting these things on curved surfaces is a bit of a challenge though a heat gun on mild setting (equivalent of a hairdryer) helps. The installation certainly looks 'interesting'. Kind of neat and kind of odd at the same time. Certainly not something you see every day. But hey, if it proves functional.... Maybe this will be the new 'bling' and I'm starting a trend here? :) We'll see.