Neck braces don’t make you safe

Yesterday, I was at Sonoma Raceway for a 24 Hours of Lemons race. I wasn’t racing, but I was working as staff at both gear tech and pit-out. At pit-out my job is to ensure the following:

  • The car has the proper event sticker
  • The driver is wearing a driver’s wrist band
  • The driver’s helmet has an inspection sticker
  • The harnesses are tight
  • The neck brace is attached appropriately
  • Other shit looks okay

Not all racing series do these checks. In fact, I think it’s kind of rare. A couple weekends ago, I was at the Lucky Dog race at Thunderhill, and the only checks were for stickers and wrist bands. Nobody put their head into the car or tugged on straps. We do that in Lemons, and I think it’s a good idea. I personally noticed the following:

  • ~5 fire systems still had their safety pins inserted
  • ~10 drivers didn’t have their neck devices connected
  • 1 driver didn’t have a wrist band
  • 2 cars had harnesses buckled way too high (stomach instead of hips)

I saw a lot of cars over the weekend, and I’m estimating that ~3% of cars have done something egregiously wrong. Nobody was wearing tennis shoes this time, but shit like that happens if you look for it.

Part of my usual routine is to tug on the front harness straps and then reach around the helmet to tug on the neck straps. About 1/4 of the time, the harness straps are too loose. As noted above, every once in a while one or both neck clips are not connected. But then I started to notice that there is quite a bit of variability in how loose the neck straps are. So I started a new routine and asked each driver to “nod your head forward” or “pretend you’re in a crash”. If the neck device is installed correctly, the helmet’s range of motion will be stopped as the tethers reach their limit. Sometimes the helmet isn’t stopped by the tethers even when the clips are in…

HANS

All of the HANS brands devices worked as intended. When you bob your head forward, the tethers stop the head from going too far. The tethers are anchored on a collar that extends above the shoulders. I like this design because the tethers go straight back when engaged. Also, you can turn your head side to side freely as you drive. However, the downside of HANS is that they offer zero protection from side impacts. If you have a halo seat, your head is protected by the seat wings. However, I estimate that only 10% of cars have halo seats. Should everyone use a halo seat? As long as you can still get out of the car easily, yes. But if the halo means you can’t get out of a burning car, I’m not sure I’d get in there. Alternatively, use a neck device with some side protection.

NecksGen

I’ve owned 2 NecksGens, the Rev and the Rev2 Lite. The former was non-adjustable and the tethers were really restrictive. You can turn your head only a little side to side.  This takes some getting used to, and I can imagine some people feeling claustrophobic. On the plus side, they provide protection from side impacts. Yay! The newer units are adjustable. That flexibility allows it to fit people of various dimensions, but it leaves the user to choose the proper length. I use the shortest setting to provide maximum protection. But I noticed that not everyone else does. I saw a couple that were so loose that they probably didn’t provide any protection at all.

Simpson Hybrid

The really cool feature of these are that the neck restraint attaches to the body rather than the harnesses. So you can use them with 3 point belts in your street car if you want to (probably a good idea for HPDE). The straps are adjustable both down and back. I saw one where the down straps were tight and the back straps were so loose I could have rolled them around my fist. Certainly that’s not how it’s intended to be fitted.

Z-tech

There are 2 selling points for Z-tech (1) the hardware itself is adjustable, not just the straps (2) they are the least expensive. These are popular, and because of that I probably saw the most too-loose straps on this device. Like the NecksGen, they offer side protection when the straps are properly adjusted and no protection when the straps are loose.

Simulate a Crash

Neck braces don’t make you safe, you do. After you strap in and are good to go, make a final check for your own safety. Nod you head forward to simulate what your head would do in a crash. Ensure that your helmet is restrained by the tethers. If you find your range of motion is unlimited, please don’t go on track. You could lose your head out there.

Silliness

This was the extent of my driving at Sonoma.

Car or driver?

One of the shockers at the last Lemons race was that the winning car won by so may laps. Usually the winners are separated by 1 lap, not 9. Is the “Shake and Break” E30 vehicle that much better than the rest of the field or do they have better drivers? It’s hard to answer this question without having the same driver in both vehicles. But I’ll try anyway.

Saturday

The weather on Saturday was pretty consistent, and with ~110 cars there wasn’t that much traffic. That means that lap times should be a reasonably accurate indicator of performance. But performance is a combination of driver and vehicle. To separate the two, I segmented the laps based on the driver. I don’t know which driver was in when, but every driver change involves a long-ish pit stop, so I simply called each driver change a new driver. I’ve included the fastest lap and the median lap below (in seconds, not minutes:seconds). Laps longer than 300 seconds were removed because those represent either a pit stop or some extended full-course yellow or even red flag.

Given the similarities between the Shake and Brake #1 and #4 drivers, I think they are the same person (Anthony Zwain).

  • Shake #1: fastest 201.687, median 210.80
  • Shake #2: fastest 213.709, median 221.25
  • Shake #3: fastest 210.30, median 216.64
  • Shake #4: fastest 204.18, median 209.54

Here are Eyesore’s times. I think they ran 4 different drivers.

  • Eyesore #1: fastest 222.95, median 229.68
  • Eyesore #2: fastest 221.10, median 230.74
  • Eyesore #3: fastest 209.66, median 216.56
  • Eyesore #4: fastest 210.09, median 215.60

Rather than comparing laps between cars, let’s look at the variation within each team focusing on the median. The Shake #1/#4 driver laps in the 209-210 range. The #3 driver is typically ~6 seconds behind, and the #2 driver is another ~5 seconds behind. There’s a heck of a lot of variation between the drivers! The Eyesore times show that the #1 and #2 drivers are pretty similar to each other and ~14 seconds behind the #3 and #4 drivers. That monstrous gap represents a 6% difference in lap times, or about 2 laps per stint. The Shake #1/4 driver is around 3-5% faster than the #2 & #3 drivers, or 1-2 laps per stint. After some sketchy mathematics, I come to the following conclusion: if you remove the fastest driver from Shake and remove either of the slowest drivers from Eyesore, the result would be Eyesore winning by ~1-2 laps.

Sunday

Sunday was a little damp early, then rainy mid-day, then drying, then dry. A wet race is very different from a dry race. It’s more about the driver than the car. Let’s look at what happened in the rain. This time, we’ll look at the graphs at SpeedHive. There was a red flag in the middle of Saturday, which you can see as the big spike in lap times near lap 60. This was preceded by some full course yellow. Note that the peaks of Eyesore (orange) and Shake (white) aren’t aligned because the graph is based on laps, not time of day. By the time the red flag occurred, Shake was already well ahead of Eyesore. Look towards the right side of the graph and you can see the baseline swells. This was when it was really wet. During this period the lap time differences are really interesting. At the start, the Shake driver is lapping much faster than the Eyesore driver, maybe 15-20 seconds. But then they pit and the next drivers are doing very similar times. If there’s a big difference between these cars, it’s not apparent from the lap times.

Conclusions

I don’t think the Shake & Break E30 is anything special. If it was, you would have seen that at the last 2 Sonoma races. However, in those 2 races, they were slower than Eyesore. The reality is that Shake brought in an exceptional driver and ran a clean race. There’s a huge difference among drivers on the same team and when you add the rain, there’s more than enough variation to explain the 9 lap difference.

Lemons Telemetry Analysis

After a race I like to look at telemetry. It shows what each driver is doing. It’s important to also run video so you can point at a corner that is 10 mph off and say “there was a yellow flag”. As usual, my telemetry is recorded with an AiM Solo DL and I view it with Race Studio Analysis. I’ve taken a screen shot of the fast laps of each driver (actually a pair of fast laps) with my fast lap as the reference lap (black line). The screen shows three graphs (1) GPS speed (2) engine RPM (3) time delta. Ideally, I’d love to have brake pressure and steering angle, but these are generally enough to infer what’s going on inside the cockpit.

One of the first things to note is that the blue driver’s RPMs are so much lower. The blue driver shifts well before he needs to. However, this doesn’t impact his speed or lap times very much. The red driver shifts much more often and is in 2nd gear several times, also not affecting lap times very much. When in doubt, drive the higher gear.

None of these laps were completely free of traffic. The red driver lost ~4 seconds in T3W to a yellow flag, for example. You can also find GPS errors where the speed is clearly recorded incorrectly for a brief time. That’s why it’s a good idea to examine multiple laps and have the corresponding video.

The biggest issue I find in the driving is that the green and red drivers slow down too early and too much in the faster corners. They do okay in the slow corners, and their final speeds may be as good as the reference lap. In slow, out fast, does actually lead to high speeds on straights! But in slow also leads to throwing away speed, and in a momentum car with very little engine, that’s a no-no. The better mantra is: in on the limit, out on the limit. That’s easy to say, but not easy to do.

Exiting a corner on the limit is like tightrope-walking; entering a corner on the limit like jumping onto a tightrope while blindfolded. — Mark Donohue

So how does one get better at jumping on a tightrope blindfolded? Do I really need to say it? Practice. And where does one practice such a dangerous activity? Do I really need to say it? Simulation.

Lemons thoughts

Some random thoughts about the last Lemons race.

Corner workers make mistakes

Going into the race, we knew that we had to minimize black flags. Everyone needs to, of course, but our car was much slower than anything else in B class and any black flag was going to put us out of contention. Sadly, we got two in the first stint. Neither one was earned. In Lemons rules, you’re allowed to pass after a yellow flag station if the mess is cleaned up. We did that and got flagged. That’s a judgement call on both sides, and given that, we should have been more careful. The second black flag was either for contact or for going 4 off. Neither of which happened, but the corner worker at T5 couldn’t see that easily.

Tuning

A couple weeks ago, the car worked great with 225 width RS4s on the front and 205 width RT615K+ on the back. I sort of destroyed one of the tires by overheating it and couldn’t run that set in the race. So I got some stickier front rubber in the form of 225 width 595 RS-RRs. I didn’t test that combination and it turned out that the team didn’t like it. Well, actually, they hated it. The team is used to an understeering car. When you get into trouble, you lift, and the front grips again. In an oversteering car, lifting only makes matters worse. As the car owner, it’s my job to provide a car that everyone can drive. Not only would the team be faster on average, they would also be safer and have more fun driving. We did eventually change the rears to get more grip and then later switched out the fronts for even less grip. Everyone but me liked it better.

Rain

Check the last post to see a video of me working through the field on a wet Sunday. I passed a hell of a lot of cars and in return was not passed. Here’s another video from our team a little later. It takes our driver a couple laps to acclimate to the wet conditions and then he proceeds to destroy most of the field.

 

The Yaris was one of the slowest and least sporty cars in the event. Why were we so much faster in the rain? Is it because we have extensive experience in the rain? I can’t speak for Danny, but I certainly don’t. I’ve only driven in the rain a handful of times. Maybe 3 hours total, and in other cars, not this one. So what’s the secret?

On my skills page, I used to have an ABC ranking system that asks the following simple question. When the car begins to slip, what do you do?

  • C drivers slow down
  • B drivers maintain speed
  • A drivers speed up

I think rain robs people of confidence. Lack of confidence can turn an A driver into a B driver or a B driver into a C driver. How does one gain confidence? Training. Like I said, I haven’t done much rain driving. So where do I get my training and the confidence that comes with it? Simulation, of course.

Lemons is changing

The C class has dwindled to just a few teams. And there used to be lots of teams sporting ridiculous themes. Our old MR2 was one of those silly cars and was just featured in the 24 Hours of Lemons Hella Sweet Car of the Week. Back then, our MR2 was put in B class with a couple penalty laps. Today, it would go into C class. I think Lemons has become a victim of its own success. Originally, Lemons was a parade/party poking fun at high performance cars. But over the years, racers have changed its culture. Part of that comes from competing series like Lucky Dog, ChampCar, AER, and WRL, where cars don’t have to be cheap and aren’t expected to have silly themes. The teams that do endurance racing tend to race all series. Now when you look over the Lemons grid you see sleek cars with $800 airfoils instead of cars shaped like boats with stuffed animals hanging out of them. While it’s true that I didn’t dress up my car or body with humorous artwork, I did bring a Toyota Yaris. But next time we’re going all in and “bringing back stupid”.

Race Report: Lemons Thunderhill

I’ll be updating this post each day.

Thursday – arrival

In the picture below you can see how simple my race operation is. I flat tow my Yaris behind a 3.0L Ranger. It’s a very flat route so the 145 hp Ranger has no problems towing the car and gear. I arrived at the track at 4:30 the day before the test and tech day to try to get a good pit spot. I wanted something under the awning so I could shelter the pit from sun/rain. Mission accomplished.

Friday – test and tech

Tech was a breeze. The car has raced in several other series and all the safety issues are well sorted. We got into the B class with zero penalty laps. That was what we expected.

We had decided that the full test day was too expensive. $349 for 1 driver and $149 for each additional. We considered doing the half day at $249 + $100 but then decided to play a joke instead. People walked by and  puzzled: “why is the wing on the front”. We dead-panned “it’s front-wheel drive”. The look of disbelief on Daniel and Mario’s faces was worth the effort.

The weather forecast changes hourly. The latest news is that Saturday should be dry all day with a high of 78. Sunday may be wet in the morning. I told the team I get to drive the wettest stint. That may screw up driver order, but as team owner, I’m putting my foot down on that. There’s no way I can keep up with the fastest cars on a dry track, but give me puddles and let’s see who comes out on top.

Saturday – race day

The race day didn’t start the way we wanted. Our first driver got 2 black flags. One of them was for going off track to avoid a collision. I’ll take a black flag over dents any day. But 2 black flags pretty much put us out of contention. Also, there was some blisteringly fast B cars we could never catch. Our second driver didn’t like the way the car was driving. Actually, neither did the first driver. When I asked if the rear had no traction, he said neither end had traction. Puzzling. So we decided to turn the rest of the race day into a tuning day.

Mario went out and came back in after a few laps complaining that the car was oversteering badly. We were running Federal 595 RS-RR 225/45/15 15×9 on the front and Falken RT615K+ 205/50/15 15×7 rear. So we decided to switch the rears out for a stickier compound: Brigestone RE-71R 205/50/15 15×7. This time he stayed out a while and had a great race with a pickup. When he came back in, he said the car was much more neutral now and that I should get in to see what I thought.

The first thing I thought was the brakes are still mushy. The pedal starts hard but just mushes out and goes to the floor. That’s really disconcerting because it gives you very little brake feel. And without a firm pedal, it’s pretty hard to heel-toe shift. Oh well, I just did more straight-line braking and eased in the clutch. Not ideal, but I’m okay working around problems. It’s likely an aging master cylinder.

The next thing I thought was that the 225 RS-RRs 15×9 aren’t that much different from the 205 15×7 I had run in earlier races. The tires don’t actually feel very fast. Part of that is because they are miserable under braking. They slide way too easily. They aren’t a particularly loud tire, like say the NT-05, and in 225 they are definitely on the quiet side. I started to understand why driver 2 thought the car had no grip on either end. The RS-RR doesn’t feel like it stops very well, so it appears to have no front grip. But once you get into a corner, it’s side grip is really good and overwhelms the thinner and harder rear tire, leading to oversteer. Mario said it was a lot of work just keeping it on track. I didn’t get to try the 615K+ rear setup, but the RE-71R rears felt pretty well planted.

While the car felt like it had better acceleration at low speeds, surely due to the weight loss, the drag was noticeably higher. This may be because the cut down doors don’t have mirrors or the wind deflectors I added. So the inside of the car turned into a parachute. It meant that top speed on the main straight was just 90-91 mph, or about 5 mph lower than usual. That didn’t stop me from having fun though. I managed a 3:43 in my few laps on track. You can see the entire stint in the video below (quality is not good because Windows 10 Movie Maker sucks. I may re-encode this on my Mac later in the week).

Sunday – race day

The forecast was wrong. We arrived at the track to find it drying. I was expecting a lot of rain early so I could one-up some fast cars but it just wasn’t very wet. Discouraged, I decided not to drive first. Danny drove first and while he was out we got our pit crew member, Tiernan, a driving wristband. He got in the car next and despite all the warnings about the blind turn 9C that connects the East and West tracks, he did what a lot of people do, and drove straight though. When he got to the penalty box, they decided to throw the book at him. My book. I had dropped off about 15 copies of the book to be sold for the Alex’s Lemonade Stand charity. Tiernan’s penalty was to read a passage from the book while being filmed. If it doesn’t make the Lemons wrap-up video, I’ll post it here.

The rain started picking up and it seemed there was enough rain to have a bit of fun. And fun was had. I got my wish and was able to dice with the fastest cars on track… and beat them.

Mario drove next and also had a blast splashing around (in the muck and the mire). But then the track started drying and he decided it just wasn’t as much fun. We wanted to get Daniel and Tiernan back in the car one more time, so they split the time on a mostly dry track. In the end, we were 56th out of 110 entries, or something like that. After we realized we weren’t in contention, we relaxed and had a lot of fun. This weekend reminds me how much fun Lemons is. That said, Lemons is changing, and not necessarily for the better. I’ll comment on that later.

Winning B Class: part 3, performance modifications

One of the things I’ve learned from endurance racing is that the best way to improve the performance of a car is to swap or boost the engine. Ha! Well, if you look at the most successful teams, that’s what they’re doing. Well, not me. My car is 100% emissions-legal in California and will remain that way (so I can park it on the street, flat tow it, and drive it to work when my other car has issues). So if I’m not touching the engine, what can I do?

  • Reduce weight
  • Increase grip
  • Improve aerodynamics

Reduce weight

In the last few weeks, I’ve removed over 200 lbs from the car. I’ve also added a few things. Let’s take a close look at the changes.

  • -104 lbs doors. Original doors weigh 72 lbs. I bought doors at Pick-n-Pull and gutted the shit out of them. They are now 20 lbs each.
  • -38.5 lbs passenger seat, bracket, and harnesses. Not necessary for endurance racing.
  • -29 lbs battery. I replaced the 34 lb lead-acid batter with a 660 CCA lithium-ion unit that weighs 5 lbs.
  • -? side windows. The original windows have been replaced by white plastic. Not sure what the difference is exactly.
  • -12.5 lbs carpets. It’s a lot louder in the cabin now.
  • -12 lbs tow hitch. I keep a tow hitch on the car for carrying extra tires, but since I’ve got a support vehicle for this race, I don’t need it.
  • -9 lbs rear seat frame. I used to mount the fire extinguisher and cold box on the rear seat frame. The fire bottle is now mounted to the floor, which is lower and lighter. The cold box is similarly mounted to the floor.
  • -6 lbs rubber gaskets. The hatchback had a lot of unnecessary rubber. I don’t need to be weatherproof.
  • -4 lbs night racing lights. No reason to carry 4 extra lights for a daytime race.
  • +X lbs cold box. The previous cold box was a cold therapy unit I got on eBay. This one is much larger so that it will remain cold during long endurance stints.

215 without taking into account side windows or cold box.

How much faster is the car minus 200 lbs? Optimum Lap (see previous post) says only about 1 second over 3 miles. But it also reduces fuel consumption by 2%.

I also had a plan to remove the rear hatch, which weighs in at 39 lbs. That’s not a lot but it seems unnecessary. So what happens when you remove it? Does it negatively affect drag? Well, I decided to test that the old-fashioned way: yarn. The hatch comes off pretty easily, just 8 bolts. Decorating the car with yarn took a while longer. After I was done, I went for a test drive with a video camera mounted to a pipe sticking out the back of the car. What I observed was the dreaded station wagon effect. Back in the 1960s and 1970s, station wagons had rear windows that rolled down. Unfortunately, the low pressure zone at the rear of the vehicle caused exhaust fumes to swirl into the cabin, causing carbon monoxide poisoning. Clearly, 39 lbs isn’t worth carbon monoxide poisoning! Eventually, wagons were installed with wind deflectors that redirected the air spilling off the roof to go down the back of the car. While this solves the carbon monoxide problem, it also generates both drag and lift.

My next thought was to make the back of the car a bit higher.  In addition to purchasing extra doors at Pick-n-Pull, I had also bought an extra hatchback. I cut the top half off and gutted it. Since it was now a lightweight metal skin, I mounted it with a few strategically-placed zip ties. More yarn and another test drive later showed that the station wagon effect persisted. The half-hatch isn’t enough to block the back draft. And why should it be? I’ve just re-created the rear of a 1970s station wagon.

My next thought was to make a lightweight hatch with the half hatch and a sheet of plexiglass instead of glass. I decided that before I did that big job I would do a smaller job: replace the side glass windows with plexiglass. To remove the side windows, I used a guitar string garrotte. I was able to remove the window without breaking it, which meant I could used it as a template for cutting the plastic. Although I cut the plastic without any problems, it cracked when I drilled it. Grrr. After experiencing how fragile and persnickety plexiglass is, I said “fuck the lightweight hatch” and put the stock one back on. I also decided I would replace the glass windows with opaque plastic rather than clear plexiglass. Not every project is successful.

Increase grip

I’ve run a lot of tires on the Yaris from Hoosiers to Douglas. In endurance races, I often opt for a medium tire that has decent grip and wear. But for this race, I want to have the stickiest rubber possible. Most people will tell you that the cheater 200 TW tires are Bridgestone RE-71R and BFG Rival S. The other tire that’s just as fast is the Federal 595 RS-RR. Not a lot of people run the RS-RR but I have in the past and it was within a couple tenths of the RE-71R at Laguna Seca. But it’s a lot less expensive. In order to get as much grip as possible, we are going wider on the rim, from 7″ to 9″ and tire from 205 to 225. Hopefully that extra width will mean the tires don’t overheat as sometimes happens. On the rears, we’ll go with 205/50/15 RT615K+ or RE-71R on 15×7 rims.

How much more grip will we get with wider tires? I have absolutely no idea, but let’s say it’s 2.5%. So 1.025g grip instead of 1.0. That results in another second.

Improve aerodynamics

In the right context, there’s a lot to be gained with aero modifications as they can reduce drag and increase downforce. Unfortunately, it’s not that easy to measure. By most accounts, an air dam is a good thing as it both reduces drag and increases downforce. So I made an air dam using some plastic made for edging a garden. I don’t really know what values to put into Optimum Lap to determine the theoretical benefit. It could gain us 1 second. Or less. Or more. The only way to know is to test. Thankfully, there is a test day before the Lemons race.

Race Report: Lemons Sonoma

This weekend I’m at a Lemons race at Sonoma. I’ll update the post a few times during the weekend as stuff happens.

Friday

The team I’m with is pretty green. There are three noobs, one 3-race veteran, and me. Noob 1 has never driven on any track. Noob 2 has driven once at Thunderhill. Noob 3 has done some autocross and maybe a track day or two, but not at Sonoma. Lemons is the first introduction that many people have to road racing, and it can work out pretty well even for the complete novice. But at Sonoma? In the rain? Well we won’t know until we try.

The car we’re racing is an MX-3, which had an unusual 1.8L V6 engine. That engine has been swapped out for the 2.5L V6 from an MX-6. So now it’s an MX-3/6ths? The car wasn’t quite ready when it arrived on track and we spent the next 4 hours working on it. But once we got to tech inspection, it passed with no problems and they put us in the B class with zero added laps. That’s probably where it belongs. The 2.5L V6 has 160 hp and the car weighs some 2400 lbs. So the power:weight is a lot better than my Yaris. If the MX-3/6ths handles reasonably well, I think I’ll be able to run with cars in the A class.

This race is using an unusual configuration for the track. They are using the short turn 7 and the bus-stop turn 9, as Lemons usual, but the track is going all the way down to the long 11. That will add 5-10 seconds to lap times and give the high horsepower cars a bit of an advantage I think. Hopefully it doesn’t become a safety issue as the long 11 is narrower.

Saturday

The long turn 11 is a lot longer than I thought. I think it added more like 15 seconds. The spectating is better with the short 11. It turns out I did a lot of spectating. I had a lot of grading to do, so I spent a lot of time inside grading rather than outside driving.

So what about the car? Well it was a hoot, but for some good reasons and some bad. The brake pads were $12 OEM replacements and overheated very quickly. So braking zones were much longer than they needed to be. The more interesting feature was the tires. We put decent tires on the front, 225 width RS3s, but in the rear we had some 205 width RT615K. Not RT615K+, but the older ones. How old? Manufactured in 2013 old. The track was soaking wet and the combination of water plus 6-year old tires meant that every time I decelerated in any kind of corner, the back end started to come around. I spent a lot of time driving sideways on the first few laps before figuring out how to drive it. Once I did, I was pretty fast, and got passed only 1 time.

160 hp in a lightweight car is plenty of power. The only car that passed me had a turbo. The big V8s were still trying to hook up coming out of a corner when I was at full throttle. I drove 90-100% of the track in 3rd gear. There was enough power to spin wheels on corner exits in 3rd so there was no reason to switch down to 2nd. And going to 4th meant I had to use more of the terrible brake pads on the next corner. On a dry track, I think I could put this car in the top 10 without much trouble.

I forgot to shoot video. I’ll make sure I do that tomorrow.

Sunday

At the end of the day, it was a great success. Not because of our placing, which was around 100 out of 120, but because we had a lot of fun. Our casual, never-rushed attitude meant that we were safe in the pit and out on track. The only negative is that Noob 1 was fighting claustrophobia and never got on track. It’s not the first time I’ve seen this. It can be nerve-wracking getting strapped into harness and not being able to move freely. Hopefully he overcomes this. Maybe splashing in some puddles rather than jumping into the deep end would have been a good idea.

Video or it didn’t happen! At the start of my stint, the track was soaking wet, but it dried out quite a bit by the end. This clip is from somewhere in the middle. I’m in a mix with some fast Lemons cars like Eyesore, Cerveza, Hassenpfeffers, Too Stupid, and BDR. And I’m keeping up with them for the most part. Our tires were a couple years old and there was some weird noises come from the suspension, so I think I did okay for what I had to work with.

 

Winning B Class: part 2, black flags

Last week I talked about why driving in Enduro style may be our best chance to win class B. By consciously driving 1% off pace we increase fuel economy by 13%, which may save one pit stop, resulting in a 5-6 lap advantage. Driving slower also reduces the chance of getting a black flag, which I parenthetically stated would ruin our race. Which begs the question “what exactly is the cost of a black flag?” We had better answer that. By ‘we’ I mean me and brother Mario.

The Slowest Driver

Early in our racing career, our team went through what most teams go through, which is learning how to drive fast. We eventually learned how fast you can drive in a race, which is an entirely a different thing. We also had to learn about pit strategy, conserving wear items, flat spotting tires, acceptable risk, going off track, hitting other cars, mechanical damage, and of course black flags.

Different race organizations feel differently about throwing black flags. 24 Hours of Lemons is very liberal with them, they’ll throw a black flag for putting wheels off track, for any contact, for passing under yellow (there are always yellows), for driving like a dick, for behaving like a dick, for exceeding paddock speeds, and anything else they feel warrants it. Consequently, Lemons racing is quite safe, because they sit down the idiots and give them a time out, or give them some ridiculous task that takes forever.

On the other end of the spectrum, ChampCar is more loose about “racing incidents” and generally doesn’t care about putting wheels in the dirt or minor contact. We brought the ChampCar judges video footage of an EC car (EC stands for Exception Class, meaning the car doesn’t fit into the competition rules and is just out there for fun) that barges into us mid-corner and almost takes us out. The officials really didn’t care. But I guess that goes both ways because we’ve never received a black flag in ChampCar, either.

But to get back to Lemons, in our first race and we were driving a MR2 with a wooden boat wrapped around it. You could bottom out the suspension by leaning on it, and it was making maybe 90 hp, but that wasn’t why we didn’t place well, it’s because we got hammered with black flags. After too many infractions (mostly passing under yellow, but also going four off), Judge Phil gave us our sentence: write out “you can’t win a race in one corner but you can lose one” 100 times. On both sides of the car. Right-handed on the right side and left-handed on the left side. That may not have been the actual phrase, but it was something like that.

In our next race, some of us were still collecting black flags, most of which were a result of driving too close to the limit. And by that I mean not just the limits of the track or adhesion, but physical and mental limits as well. In order to demonstrate how much this affects lap time, we did some work in a spreadsheet.

A typical 2 hour stint is less than 120 minutes because nearly every stint has some FCY (full course yellow) time. So let’s say that a stint has 100 minutes of spirited driving. At a 2 minute pace, a driver can complete 50 laps during this time. How many laps can be completed if one also picks up a black flag? Some black flags are only a few minutes and some are quite long if there are other cars also being attended to. At some tracks the race stewards are outside the timing loop so you lose whatever lap you were on. 8 minutes sounds like a good average.

The cost of a black flag is therefore 4 laps and the black flagged driver can complete only 46 laps. You know who else completes 46 laps? The driver way off pace lapping at 2:10. Getting a single black flag will turn the fastest driver into the slowest driver. Once getting a black flag, there’s no way to drive fast enough to make up for the transgression. That would mean driving a 1:50 pace or faster. That might not be physically possible, and if you’re getting black flags at a 2:00 pace, you’ll pick up a dozen more driving at 1:50. The second black flag will set your actual pace to 2:23.

How hard should you drive?

Regardless of how skilled you are, the more you push yourself, the greater your risk. To examine this, let’s look at the Assetto Corsa world records at the RSR LiveTiming site. As I’ve done in some previous posts, I’ll use Brands Hatch Indy and the NA Miata as the source. The top driver, Marius Golombeck, has somehow manged a blistering 59.757 lap time. That’s almost 1 second faster than I’ve done (1:00.653). He’s logged 181 laps to achieve this. And in doing so, he’s had the equivalent of 113 black flags (invalid laps from going off course). So even aliens can’t manage to stay on track when they’re driving 10/10ths. And this is just a time trial without any traffic.

So if you shouldn’t drive 10/10ths, what is acceptable? I can lap all day with zero risk of self-inflicted harm (there’s never zero risk with other people on track) when I’m 1-2% off pace. Hey, that’s like the Enduro pace from last week. Not only can it cut 1 pit stop (gaining 5-6 laps), it also reduces the chance of getting a black flag (costing 4 laps). You don’t lose much by waiting for a safe time to pass a slow car, giving extra space to less experienced drivers, pointing by a train of faster cars, or staying off the curbs and grass. Not doing those things could cost you the whole race if you pick up a black flag and find yourself making repairs.

In a typical amateur endurance race, drivers may have different capabilities. Everyone needs to cut their own 1-2%. The benchmark can’t be the fast driver. I recall a race at Willow Springs where my comfortable pace was 5 seconds ahead of a teammate who drove over his limit, crashed the car, and ended our race. Egos and red mist sometimes win over reason. To combat this, clever teams have put the driver’s cell phone in a bag on the front bumper or set a fastest lap anti-bounty (fastest driver pays $100 for bragging rights). We haven’t done these things yet, but we talk about it.

Mario’s Advice

Here’s what I do: Drive at a pace where I have total situational awareness and a huge margin for other drivers fucking up; Follow drivers that are a bit slower than I am, for as many laps as they let me; Point-by everyone who’s on my bumper; Be kind to the car; Exit the car after my 2-hour stint feeling refreshed – not tired, not energized, not angry, not pumped, not frustrated, but refreshed and ready to get back in.

Ian’s Advice

Have a mindset that the race is safer and more fun for everyone (not just you) because of the way you drive. Race with people, not against them, and for fucks sake, don’t have a competition within the team. Drive 70% of the time at 7/10ths, and when you need to step it up a notch, go to 8/10ths not 8/8ths.

Winning B Class: part 1, fuel consumption

When I built my 2007 Toyota Yaris for racing, I aimed it at the SCCA B-Spec rules. Only after competing in an SCCA sprint race did I realize that sprint racing is not for me. It’s much more expensive per hour, the “win every corner” mindset makes it more dangerous, and it’s lonely not hanging out with a team. With that in mind, the decision was clear: re-build it for endurance racing. Sadly, it’s a little too slow for most applications. In Lucky Dog, it’s slower than most class C cars (when it doesn’t get protested for being too new). In ChampCar, the build is 120 out of 500 points so there are plenty of points to work with. But in order to compete it would take an engine swap or forced induction. Given that I want to keep it emissions legal in California, these options are mostly out of the question. Neither World Racing League nor American Endurance Racing league run events out West, so the target is Lemons. In 24 Hours of Lemons, it would probably be placed in class B. Could we win the B class with a little luck and a lot of planning? Well, this post is the first in a series where we document our efforts.

So what are our advantages? Reliability and economy. Unlike half of the cars in B class, we have a very good chance of running the whole 14.5 hours of a typical race (8 hours on Saturday and 6.5 hours on Sunday). However, we will be competing against much faster cars. We need to be on track as much as possible. This means zero black flags, of course, but it also means as little time as possible in the pits. In fact, we’re hoping to cut out one pit stop.

Most endurance driving stints are 2 hours or less. Lucky Dog and ChampCar actually limit drivers to 2 hours. Lemons has no such rule. However, most cars burn fuel fast enough that they pit between 1.5 and 2 hours. That means that a typical team will run 4-5 stints on Saturday and 3-4 stints on Sunday. I believe our best chance to win means driving only 3 stints on each day. The question is, can a single tank of fuel last 2 hours and 40 minutes on Saturday?

Our previous racing at Thunderhill, Laguna Seca, and Buttonwillow shows that the Yaris burns about 4 gallons per hour. With its 11.1 gallon fuel tank, it should be able to run 2:45. That’s no problem for Sunday but Saturday could be. If our calculation is off by 10%, we might find ourselves running out of fuel, and there would be no chance of winning if that happened. So we need to figure out how to extend our range.

The simplest answer is to install a fuel cell. That would instantaneously solve the range problem but would bring up new problems. They’re expensive. It would require removing the stock fuel tank and fabricating a new structure. The car would also no longer be street legal. The center of gravity would be higher. Too many negatives, so I’m not getting a fuel cell. Lemons does not allow one to modify OEM fuel fillers, so I can’t increase capacity with a fat intake tube either. So if we can’t increase fuel capacity, we’re going to have to increase efficiency.

Economic driving

Who knows how to get the most miles from a tank of gas? Hyper-milers. I’m sort of a closet hyper-miler myself. On the street, I often drive under the speed limit, conserve as much momentum as possible, pump my tires up pretty high, and draft trucks on the highway. I don’t go as far as making aerodynamic improvements though. But we will on the racecar. However, that’s a topic for another day. Today we are going to consider the act of racing more conservatively. The driving can’t change so much that we do more harm than good, though. We have these two connected questions to consider.

  1. How much fuel do we save by changing our driving style?
  2. What style of driving optimizes our chance of winning?

To answer these questions, I’ll be using Assetto Corsa, Brands Hatch, and the NA Miata. While I do have a Yaris model for Assetto Corsa, I don’t think it’s very accurate. The NA Miata is one of the highest quality models and besides, Miata Is Always The Answer. The car is loaded up with 5 liters of fuel, “Street” tires at 30 psi, max camber, and zero toe.

So let’s define a few different driving styles.

  • Hard – Hit the brakes hard. Hit the throttle hard. Steer like a mad man. In slow, out fast. Brake in a straight line. Shift at red line (7k). Lots of amateur racers drive like this, especially those in powerful cars. Clearly we’re not considering this, but I wanted to investigate the efficiency of a typical sucky racer. Intensity 9/10ths. Intelligence 3/10ths.
  • Soft – Conserve momentum as much as possible with early apex lines. Coast slightly before braking zones. Shift at 6K and choose a higher gear if there’s any question. Steering corrections are unnecessary driving like this. Intensity 5/10ths.
  • Enduro – Drive fast but with a lot of margin for error (not much yaw). Shift at 6.5k. Use lots of trail-braking but only a little brake-turning. Intensity 7/10ths.
  • Sprint – Drive faster with plenty of yaw. Still keep some safety in reserve. Shift at 7k RPM. Intensity 8/10ths.

The most interesting finding for me was that Soft driving increased fuel economy by an amazing 40% over Hard driving while having nearly identical lap times. My typical Enduro style results in decent fuel economy and speed. I’m only about 1% off my Sprint pace but my economy is up 13%. Compared to driving Soft, Enduro is 3.3% faster at the cost of 22% less economy. So which style is best for endurance racing? Is it better to drive slowly to get a tank of gas to last 148 minutes, drive as fast as possible while only getting 103 minutes, or something in between?

Style Laps Fast Median Laps Minutes
Hard 10.3 63.96 64.18 98.88 105.8
Soft 14.5 63.84 63.97 139.2 148.4
Enduro 11.9 61.31 61.91 114.2 117.9
Sprint 10.5 60.84 61.29 100.8 103.0

The track is live for 480 minutes on Saturday. But not all of those 480 minutes are hot. Lemons does live towing and when there are several tow trucks on track at once they will fly full course yellows. Sometimes that goes on for 5 minutes and sometimes for 30. I recall one race where they threw a red flag and I waited nearly 20 minutes with the engine off. It’s hard to predict how much of the 480 minutes are green and how much are yellow. So we need to investigate what happens with 10 to 120 minutes of yellow flag time, which results in 470 to 360 minutes of race time.

The next thing to consider is how many driving minutes there are. The car isn’t lapping when it’s in the pits. My calculations use a pit stop time of 10 minutes. It doesn’t take that long to fuel a car and change drivers, but Lemons pit stops occur in the paddock, outside the timing loop on the track. So every time you pit, you lose 1 lap in addition to transit time.

Taking into account lap times, fuel burn, yellow flag time, and number of pit stops, we arrive at the table below. I have highlighted the driving style that produces the most laps in red.

Yellow Hard Soft Enduro Sprint
10 401 412 426 420
20 392 403 416 411
30 383 393 407 401
40 373 393 397 391
50 364 384 387 381
60 364 375 377 372
70 355 364 368 372
80 345 356 358 362
90 336 347 348 352
100 327 337 339 342
110 317 328 329 332
120 308 318 319 323

When Enduro beats Sprint, it does so by 5.67 laps on average. Conversely, Sprint beats Enduro by 3.67 laps on average. The difference comes down to how many stints there are. Enduro sometimes runs one less stint, and when it does, it has a huge advantage. It doesn’t impede lap times that much and has the added benefit of reducing fatigue and the chance of a black flag (which pretty much guarantees we won’t win B class). Driving Soft never wins. It can be as much as 10 laps better than driving Hard, and there are a few situations (highlighted in blue) where it is better than Sprint. But it never beats Enduro. There isn’t much point in driving super Soft. The hyper-miler in me wanted that to be useful, but it isn’t.

Telemetry or it didn’t happen!

The line colors are:

  • Red Hard
  • Blue Soft
  • Green Enduro
  • Black Sprint

The panels from top to bottom are:

  • Brake pressure
  • RPM
  • Speed
  • Steering angle
  • Throttle
  • Time delta

Click on the image to open it in a new window and then follow along with the text below.

There are 4 braking zones (top panel). In Soft style I only applied brakes in 2 of these. Note how low the RPMs are in general. You can also see long periods of coasting in the 5th panel (throttle). But the speed graph (3rd panel) isn’t that terrible. Driving economically is a kind of intellectual challenge, which is why I hyper-mile in real life. I have to do something to make street driving entertaining.

Hard style sees me sawing the fuck out of the steering wheel (4th panel) and mashing the brake and throttle pedals mercilessly. The brake trace (top) shows early and hard application of the brakes followed by no trailing pressure. Just on/off. It’s not a fast or economical way to drive.

There isn’t a huge difference in driving style between Enduro and Sprint. I use more brake pressure in Sprint mode to turn the car and I also choose a lower gear in a couple of places. I consciously take an earlier apex line in Enduro to favor momentum over engine.

Passing Thoughts: Part 2 (Rules)

Every racing organization has its own set of rules about passing. Let’s take a look at some of them in order from brief to verbose. Next week we’ll talk about how the rules are actually used and some best practices as a result.

Lucky Dog

Lucky Dog prides itself on its brief rulebook and the passing rules are no exception.

  • 12. h. Passing. The passing vehicle is 100% responsible for the careful and safe preparation, planning and execution of the pass…period. If you are about to be passed, it’s most helpful to give the passing car hand signals as to which side you will allow them to pass on. But most importantly, you need to hold your line and remember that the other car is responsible for safely getting around you.

Lemons

Lemons is tongue-in-cheek as usual. They don’t specifically define passing rules. The arbitrary nature of the rules and penalties turns off some drivers.

  • 6.0: Penalties: Black-flag penalties are assessed for dangerous behaviors and/or being a douche. These behaviors include, but are not limited to, contact for any reason; wheel(s) leaving the pavement; speeding in the pits; missing/ignoring a safety flag; racing to the yellow or red flag; overly aggressive driving; hitting a wall, cone, tree, safety vehicle, the track restaurant, etc; lack of car control; thinking the line has a deed and you own it; unsportsmanlike conduct; annoying the hell out of us; annoying the hell out of everyone else; etc.
  • 6.1: It’s Always Your Fault: Lemons is an all-fault environment. You are 100% responsible for what happens while you’re at the wheel. Think you’re the hittee, not the hitter? We don’t care. Think you’ve been wrongly accused? See the part where it says “we don’t care.” Your job is to stay out of trouble. If trouble finds you, take responsibility like a grownup and figure out how to avoid it the next time. This ain’t the damn SCCA.

SCCA

Despite being a rather large and complex entity, the SCCA rules are quite brief.

  • 6.11.1 On Course Driver Conduct
  • A. Drivers are responsible to avoid physical contact between cars on the race track.
  • B. Each competitor has a right to racing room, which is generally defined as sufficient space on the marked racing surface that under racing conditions, a driver can maintain control of his car in close quarters.
  • C. Drivers must respect the right of other competitors to racing room. Abrupt changes in direction that impede or affect the path of another car attempting to overtake or pass may be interpreted as an effort to deprive a fellow competitor of the right to racing room.
  • D. The overtaking driver is responsible for the decision to pass another car and to accomplish it safely. The overtaken driver is responsible to be aware that he is being passed and not to impede or block the overtaking car. A driver who does not use his rear view mirror or who appears to be blocking another car attempting to pass may be black flagged and/or penalized, as specified in Section 7.

ChampCar (formerly ChumpCar)

The ChampCar rules are very similar in wording and spirit to the SCCA rules. But they add a few specifics about driving on the racing line and blocking. They also further define what a complete pass is.

  • 7.2. ON-TRACK DRIVER CONDUCT
  • 7.2.1. It is the responsibility of all drivers to avoid physical contact between cars on the race track. All competitors have a right to “racing room” on the marked racing surface. “Racing room” shall be generally defined as sufficient space on the marked racing surface to allow a competitor to maintain control of his/her car.
  •  7.2.2. The responsibility for passing another car and accomplishing that pass safely rests with the overtaking driver. The driver that is about to be overtaken has the responsibility to be aware that he or she is about to be passed, give hand-signals and shall not impede the overtaking car.
    • 7.2.2.1. The driver being overtaken should, at all times, remain on their racing line unless the car is impaired and is unable to maintain an adequate racing speed.
    • 7.2.2.2. The driver being overtaken shall not block. Any driver who fails to make use of their rear view mirror, or who appears to be blocking another car seeking a pass, will be black flagged and/or penalized.
    • 7.2.2.3. It is the responsibility of the overtaking car to prepare for, plan and execute a FULL and COMPLETE safe pass. The definition of a full and complete pass is when the overtaking car has extended a lead of approximately one car length ahead of the vehicle being passed.

World Racing League

WRL is similar to those above, but adds specific language about the order of precedence when defining fault. They also further define racing room.

  • 2. Racing Rules:
  • a. Contact: World Racing League is a non-contact racing club. To avoid contact, all drivers should maintain racing room at all times and in all situations. “Racing room” is defined as allowing all competitors room to maneuver their car on the racing surface, or more simply put, giving your competitor a lane to race in.
  • b. Passing: Safe and drama-free passing requires that everyone adhere to the following rules. For the purpose of defining at-fault contact while passing, the passing rules are weighted in the following order:
    • Making a pass: It is your responsibility to plan and execute a safe pass, maintain racing room at all times
    • Being passed: It is your responsibility to check your mirrors, hold a consistent line, be predictable, use hand signals and to maintain racing room at all times
    • Position: For the purpose of determining position, a car attempting a pass is considered to have established position once it’s front axle has pulled even with the rear axle of the car being passed.
  • c. Safe pass: A safe pass is defined as a pass where no contact takes place and no car involved in the pass spins or leaves the racing surface, because all parties maintained racing room at all times. If a car is next to you and you deprive him of racing room by causing contact or “squeezing” him off the track, you have violated safe passing etiquette and will be Black Flagged

American Endurance Racing

AER rules are pretty similar to those above, but add that the slower car should indicate which side they want to be passed on that cars in different classes should not interfere with each other.

  • 9. Passing
  • 9.1. Every competitor has the right to racing room, which is defined as sufficient space on the paved racing surface that under race conditions a driver can maintain control of his car in close quarters.
  • 9.2. The car entirely in front has the right to choose any position on track, so long as it is not considered to be blocking. Blocking is defined when a driver makes two or more line changes in an attempt to prevent the trailing car from passing.
  • 9.3. A driver who does not use his mirrors or appears to be blocking another car attempting to pass may be black flagged, and may be penalized.
  • 9.4. Ultimately, the decision to make a pass and do so safely solely rests with the overtaking car. The car being overtaken should be situationally aware of the fact that they are being overtaken, and not make any sudden or unpredictable moves or blocks to impede the ability of the overtaking driver to pass.
  • 9.5. When possible and when it becomes apparent that a pass is going to occur, it is a courtesy and strongly suggested that the car being passed to indicate to the passing car on which side they would like to be passed on.
  • 9.6. Cars who are not racing in the same class are strongly encouraged to work with each other to effectuate a prompt and safe pass. Drivers should be aware that they may come upon a situation where two other cars are in a heated battle in their respective class and should try to accommodate any passing required without holding up that battle. It should be noted that this applies to classes faster and slower than you.

NASA

NASA has the most detailed rules on passing as they have several examples and rulings in the appendix. It’s very useful to read this section even if you have no interest in racing with NASA.

  • 25.4 Rules for Overtaking 25.4.1 Passing General
    The responsibility for the decision to pass another car, and to do it safely, rests with the overtaking driver. The overtaken driver should be aware that he/she is being passed and must not impede the pass by blocking. A driver who does not watch his/her mirrors or who appears to be blocking another car seeking a pass may be black-flagged and/or penalized. The act of passing is initiated when the trailing car’s (Car A) front bumper overlaps with the lead car’s (Car B) rear bumper. The act of passing is complete when Car A’s rear bumper is ahead of Car B’s front bumper. “NO PASSING” means a pass cannot even be initiated. Any overlap in a NO PASSING area is considered illegal.
  • 25.4.2 Punting / Passing in Corners
    The term “punting” is defined as nose to tail (or side-of-the-nose to side-of-the-tail) contact, where the leading car is significantly knocked off of the racing line. Once the trailing car has its front wheel next to the driver of the other vehicle, it is considered that the trailing car has a right to be there. And, that the leading driver must leave the trailing driver enough “racing room.” In most cases, “racing room” is defined as “at least three quarters of one car width.” If adequate racing room is left for the trailing car, and there is incidental contact made between the cars, the contact will be considered “side-to-side.” In most cases, incidental side-to-side contact is considered to be “just a racing incident.” If, in the case of side-to-side contact, one of the two cars leaves the racing surface (involuntarily) then it may still be considered “a racing incident.”
  • 25.4.3 Right to the Line
    The driver in front has the right to choose any line, as long as they are not considered to be blocking. The driver in front loses the right to choose his or her line when the overtaking driver has their front wheel next to the driver. Note: This rule may be superseded by class specific rules. As an example, once the lead car loses the right to choose the line that driver cannot “squeeze” another vehicle off of a straight away claiming the “three- quarters of a car width.”
  • 25.4.4 Blocking
    A driver may choose to protect his or her line so long as it is not considered blocking. Blocking is defined as two (2) consecutive line changes to “protect his/her line,” and in doing so, impedes the vehicle that is trying to pass with each of the two (2) consecutive movements. Drivers are encouraged to check with the Race Director for a full explanation before the start of the race.