04/28/08 In the Spring trackdays come one after the other. By the end of May it's pretty much over until September so we're trying to get a few in while we can. Today is BMW day, me instructing again and M running DarkHelmet. Larry brought out the Evo and the Exige, and even Tristan made an appearance with his 2002. It's an interesting lineup.

The forecast was confused as always but basically they were saying rain and 46 degrees. The day did start out on a wet track (so I got to play with the EVO which is on rain tires - FUN!). By 10 am it was dry and by the end of the day it was 68 degrees and sunny. Weather on the iphone said it was raining. The usual.

This was a day of much learning. I played with some different lines and strategies in the Exige. Didn't get any faster but I think the new approaches will ultimately pay off, I just need to get more used to doing things this way. M also made very good progress and despite yet another set of brake pads going away she put the various things I've been teaching together and pulled off a couple excellent sessions. In fact the marginal brakes turned out to be a blessing because she had been overbraking for some corners and this gave us a perfect opportunity to work on increased entry speeds. One or two more trackdays in Intermediate and she'll be ready to move up to Advanced.

Continuing with the learning theme, over the weekend M took a motorcycle riding class and got her endorsement so pretty soon we'll be doing bike trackdays together too. I'm way overdue for one.

After the trackday we had lots of technical discussions over some drinks at happy hour and then the work day starts (still have to pay the bills). Life is good.

05/15/08 Just a quick update. A friend who was also at the last trackday bought some pictures from the photographer and one of them had M driving the mini so he sent it to us. Click for larger version:

In other news the old set of KDW2s is now history. I decided to try the new Dunlop Direzza Z1 StarSpec - they're only $124 from TireRack (a commercialist reminder to use my link if you're going to buy from them ;). Just have a few street miles on the new tires so far and they seem to stick well both in the dry and in the wet. We'll see how they do at the track Monday. Got a new set of track brakepads too so DarkHelmet is all ready. Monday will also be Bikini's track debut, albeit still with a 7K redline (it goes to 11 :). Should be fun.

05/19/08 The weird weather streak continues, this time with a scorcher of a trackday - temps in the upper 80's. I ran the Atom (see its page) and M ran the Mini.

This was the first day on the new tires and M's impression of them was not favorable. She struggled to get below 1:40 (did eventually, but only just). So I ran the car in the last session for reference and only managed a 1:38.8. The obvious thing would be to blame the tires, but this is where datalogging comes in and proves very useful and educational. I pulled up the data on my best run this year, a 1:34.8 (black trace) and compared it to this one (red trace).

The thing that jumps out immediately is the huge difference in speed on the straights - about 7 mph! This is because the first run was on a 50F morning and the second run on a 87F afternoon (ok, we also had the AC on). I would certainly expect the supercharged engine to lose power with higher temps but frankly the difference surprises me. A full 4 seconds! AC is a contributing factor, I know, but I did try switching it on and off on the front straight and there didn't seem to be any noticeable difference. So most of it is due to power loss - presumably with heat and I hope that's all it is.

As far as tires go, the Dunlops do seem to be more 'squishy' and subjectively don't stick as well as the KDW2s did. Lateral g traces show a tiny bit less grip but nothing dramatic. On the plus side the tires held up really well and show little wear whereas the KDW2s (in unshaved form as these are) would have been missing chunks of tread. Just look at earlier entries on this and the previous Mini's logs. So an interesting datapoint, all this. Like I always say, I learn something every time I get out on the track. It is also nice to see that M is now only a second off my time, same-car-same-day :) She was passing everyone in the intermediate group. Couple more trackdays and we might move her to advanced.

06/06/08 I've been meaning to get a race license for years. Even took the Cascade school in 2002 and was signed off for the novice race program but never follwed through - trackdays are so accessible and convenient that there wasn't much need. But now, with all the projects moving along, I need access to test-and-tune days for development. And that means a race license is a necessity. So M and I signed up for another Cascade school and Larry agreed to loan me his Spec Racer Ford for the novice race that follows. Today was the school.

It is run similar to a trackday except with more formal instruction (there is a classroom 'ground school' the night before) and we get to do a practice race start at the end. The school is done in the regular street cars and Dark Helmet performed well as always. We brought the Rux just in case it really started pouring (and so that both of us can do the race start) but precipitation kindly limited itself to an occasional drizzle so it was another double-duty trackday for the Mini, the 29th in its not-quite-17K miles. I'm really impressed with how the car is holding up (knock on wood) - other than replacing consumables like brakes and tires it's needed nothing so far. My hat is off to BMW.

The new Dunlops are amazingly resistant to wear showing almost none despite all the abuse, although their grip is not quite up to KDW2 or GS-D3 standards. The tires are forgiving so that is a plus and they can still be drifted and slid when necessary. Overall I'd rate these as excellent for novice and intermediate track drivers but for advanced they fall a bit short in overall performance and feel while excelling in the value equation (cheap and long lasting).

Both M and I passed the school with flying colors. M was among the fastest drivers in the intermediate group. Time to move to advanced and that's exactly what her instructor recommended. We are both signed off for the novice race. My first race is this weekend and hers will probably be in a couple of months. Wish us luck :)

In terms of other cars there today, the most interesting were a green Pantera and a green Austin Healey. Neither was very fast but it was just cool to see them at the event and participating.

06/20/08 The 30th trackday for darkhelmet. I spent the whole day fussing with the Atom so M got to run it by herself. Making good progress and passing most people in the Intermediate group - next time she'll run in Advanced.

It's pretty much routine now. The usual wear items keep wearing - yet another set of trackpads and the just-replaced rotors are showing some distress. The tires are holding up surprisingly well. At least there is an upside to the somewhat reduced grip - the wear is MUCH better than KDW2s.

07/29/08 Porsche club trackday. This was M's first outing in the Advanced group and she did very well, managing to pass a few people and keep up with others including a GT3 (true, most of the many GT3s in attendance were clearly faster but not all and this IS the Advanced group). She's starting to slide the car a bit in turns and use throttle steering to get it pointed. We ran the datalogger for several sessions and I drove a session in the Instructor group for a baseline. She ended up running mostly in the 1:37s with a best of 1:37.08. My best lap was 1:35.18 with majority in the mid-to-high 1:35s (so the Dunlops are not that far off KDW2s afterall and the wear is amazing - even the fronts are still good). The details are on her page.

M is clearly an advanced driver now (but the day after tomorrow she gets to be a total novice again at her first bike trackday, having been on a motorcycle a total of 8 times so far). Of course the learning and improvement will continue but now we're after fractions of a second here and there, and aside from braking later the opportunities for gains are much harder to identify. This is where the datalogger really pays off, we'd be flying blind without it. It's going to be fun :). Today we actually discussed trading the Subaru for an Elise so that she has a trackworthy rear-driver to play with. Pretty much all her track experience has been in the Mini so far and to progress she needs to try a variety of cars. We'll see.

10/14/08 It is good to know some things still work well. The 35th trackday for DarkHelmet went perfectly. The car behaved well and was fast and fun to drive. I got into 1:34s on the Dunlops which equaled the best I've done on KDW2s. This brings me to the next thing that's working well - the tires. They are holding up amazingly well, still. We did have them flipped on the wheels and rotated around the car since the left front was starting to show wear on the outward-facing half (not surprisingly as most turns at PIR are to the right). This is how the tires look after more than 1,000 track miles, driven in throttle-steered slides through all the turns:

For anyone doing lots of trackdays I don't know of any better tire than this. Sure, there are grippier ones (any R compound) and there are those that work better in the wet (Goodyear F1-GSD3) but as far as something that works well on the track AND lasts, the Dunlop Direzza Z1 Star Spec can't be beat, at least in my experience. And yes those calipers USED to be black... :) The brakes continue to work extremely well too but they do wear - we're half through another set of track pads. The track season is pretty much done now (might be one or two more trackdays left but not sure if we'll do them).

There were several cool cars in attendance, the new M3 that ran in the novice group and an Aston V8 that ran in advanced. M now wants the M3, badly. Hmm.... I still think the Aston is one of the most beautiful cars of all time. He was running about 1:33 out there, catching the Mini on the straights but losing a bit in the corners despite being on R compound Pirellis. I don't know anything about the driver but that's about the performance I would expect from the car in the advanced group, driven by someone who is not a pro but competent. Yes, I still want one but not bad enough to actually get one any time soon.

04/13/09 The 36th trackday for DarkHelmet. Conditions kept changing dramatically throughout the day. We went from damp track to dry track to torrential downpour to hail to sunny with alternating wet/dry pavement. M started out in this car but the heat-cycled tires really don't work well in the wet (plus this is her first trackday in months) so she was pretty conservative.

Karl had the Mini next and figured it out very quickly. Fortunately the pavement was dry for most of the session and his best lap at the end of 20 minutes was 1:35.9 - almost equaling M's best in this car and within a second of my best. Very impressive for first time on this track and in this car. I'm sure with some seat time he'd do better. I wish we had that opportunity today, it would be quite educational for me. But the weather turned weird after the session and there was no fully dry tracktime until the end of the day, when I was able to get two clean/dry laps in for a best of 1:35.7. On the plot below, Karl is the black trace and I'm red.

The last plot in the picture is time slip and shows where time is lost and gained. Mine is the horizontal reference line and when Karl is ahead his trace is below it, when he's behind it's above.

The difference in driving styles is interesting - Karl gets consistently better drive out of turns while I consistently outbrake him (granted, the brakes weren't working at full capacity when he drove and we had to bleed them over lunch so it's more down to equipment than any under-braking on his part). Nevertheless, it's illustrative of how important braking is - just before entry into Turn 10 (at the cursor above) Karl is 0.3 sec ahead but on the exit of the turn, only a couple hundred feet later, he's 0.5 sec behind. The next time he's out this way we'll have to do much more extensive comparisons (and hopefully in the dp4 and dp1, too! :).

For the rest of his visit however, with our own trackday rescheduled, we'll have to contend with driving LFS over the network (I have two steering wheels and many computers). That's quite fun too, actually.