YSAR at 200 posts

This is the 200th post on You Suck at Racing. That amazing (to me) milestone requires some kind of recognition. I thought I’d use this as an opportunity to reflect on the origins and evolution of YSAR.

The Science of Driving

I first started writing about driving about 4 years ago, which was ~1.5 years after my first track day. The writing was mostly personal and I had no intent to publish it. I was trying to codify what I knew about driving as a way to help me understand it. I was titling this document as “The Science of Driving”. The title was inspired by something my twin brother said after a go-kart outing. Mario described my driving as “driving like a scientist”. Surely it was not meant as a compliment. I think it was his way of saying I was trying to put rulers on things rather than driving by feel. Well, I disagree. Not with my driving style, which I’m sure was about as smooth as chunky peanut butter, but with the idea that driving scientifically was somehow a bad thing. I believe everything is done better as a scientist. So I started writing down all that I knew about driving to begin my scientific exploration.

The document ended up at 11 pages before I got distracted with other things. Although unfinished (and in some cases not entirely correct), there are parts I’m happy with. Read it if you’re so inclined: ScienceOfDriving. The reason I got distracted was again because of something my brother said, which was loosely “Why do you keep talking about how to drive faster? The most important thing in endurance racing is not getting a black flag”. This is largely true. Once you get a penalty, you’re no longer lapping, and there’s no way to drive fast enough to make up for the lost time. So I thought “valid point, it’s time to explore why accidents happen”. So I started researching endurance racing crashes via YouTube. After I’d amassed a large library of clips, I decided I would start blogging about crashes as an entertaining way to catalog how and why they occur.

Evolution of YSAR

The first 99 posts of YSAR were focused on crash analyses. My top 5 favorite posts during this time were:

  1. The four temperaments. The writing in this post is a microcosm of my personality: eclectically nerdy with a dash of salt.
  2. Tossing the nannies. I like talking about brakes. It’s probably my favorite driving topic.
  3. Divided we fall. I like quotes!
  4. I can drive a manual. The video displays such an amazing degree of incompetence from one-handed driving, to not wearing neck protection, to unzipping his fire suit, to downshitting an automatic.
  5. S is for Style. This driver’s cool under pressure makes me jealous.

One of the failures of YSAR was trying to come up with TLAs (three letter acronyms) for the various incidents. Sometimes descriptive names and phrases are better. For example IDS/IDX isn’t nearly as expressive as “I didn’t see / I didn’t expect”. Some of the videos in that section are really great, but the posts don’t get revisited often. Ah well, live and learn.

After post #99, YSAR wasn’t just for crashes. I blogged about car building, simulation, coaching, and driving. Here are 5 instructional posts from this period that I really liked.

  1. Chalk talk: figure 8. Figure 8 drills are a lot of fun and useful too. We do this at the start of the day in the Hooked on Driving novice class.
  2. Video: Thunderhill West. I’ve only made one track guide video. I’m pretty happy with how it turned out.
  3. Backing up the corner. It’s the key to driving faster. I think it’s the thing that separates intermediate and advanced drivers.
  4. Coaching 86s. It was a fun day and nobody learns more than the teacher.
  5. An identical twin study of car racing. This post was contributed by my twin brother.

Most Popular Posts

The following posts are often at the top of the list every week. I’m not linking them because they are popular from keyword searches, not necessary insightful content (in my opinion).

  1. Product Review: Thrustmaster TS-PC Racer
  2. Simulator roundup 2017
  3. Telemetry: trail-braking

All-time Favorite Posts

My favorite posts are those that mix theory, practice, and experimentation. In Circular Reasoning, I asked the question “what is the fastest way around two cones?” I followed this up with a theoretical analysis Cones in Theory, which gave the answer “the shortest path”. This met with some skepticism. A few months later I wrote FWD Drifting: Part 2 and Cones in Practice in which I raced around cones in real life and found that the theory was correct.

Another series of posts I really liked were Math on the racing line part 1 and part 2. This brace of posts analyzes the shape of the racing line and comes up with some surprising answers. Not only does the line depend on the car, but also the available grip. I had to write some interesting code to figure this out. These math posts get hit nearly every week.

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Coaching in an Exocet

Have you heard of an Exomotive Exocet? I’ve sort of drooled over photos of these and other kit cars for some time. They look so damn cool. Exocets are built from Miatas, which are a personal favorite. While Miatas are pretty light cars, tipping the scales at around 2200-2300 lbs, an Exocet is only around 1500. At the start of the day, I was trying to choose between an ND Miata and an Exocet. I haven’t been in an ND on track yet, and was eager to check one out. I imagine I might own one some day. But how often do you even see an Exocet? Almost never. So I decided to choose the student with that car. It turns out it’s not his car, but a buddy’s.

My first experience with the car was on the skid pad for the figure 8 drill. Given that the car had the stock 1.8L engine, it wasn’t a tire burner. But the student did get to practice some oversteer and recovery. The car felt safe and fun. Then I went out with the owner in the B session and changed my mind entirely. I had an open face helmet, and the wind was really uncomfortable at 100 mph. It was so loud I couldn’t audibly  communicate with the driver. It didn’t feel at all safe. I made the mistake of hanging onto the frame at one point and got thwacked by a piece of rubber. Ouch.

I decided I couldn’t coach in that car unless I made some kind of change. I switched to a closed faced helmet and put Senna bluetooth radios in both helmets. What a difference. Problem solved. In the first on track session with my student, I drove 2 orientation laps to talk about the flag stations and such. So how does an Exocet feel? Not so different from a Miata actually. It was a little too light in the rear, which doesn’t make for an ideal car for a novice student. The major problem I had with it was the position where the A pillar bar meets the floor. The tube ends up very close to the left foot and there’s no room for a dead pedal. I’m really used to anchoring my left foot on a dead pedal. What was I supposed to do with my left foot? Hover over the clutch? Rest under the clutch? Who builds a frame that prevents proper foot positioning? Exomotive does. Maybe they expect you to reposition the pedals to the right?

Building an Exocet costs in the neighborhood of $20K and takes hundreds of hours of labor. In the end you get a unique car that is a real head turner. But let’s be clear, it’s not the ultimate track weapon. If you’ve already got a Miata, you could run circles around an Exocet with a turbo upgrade. But for the price of a Miata and turbo, you’re also be in the neighborhood of other excellent track cars like Acura RSX Type S, BMW E46/Z3/Z4, Nissan 350Z, or Porsche Boxster.

Over the course of the day, my attitude about the Exocet evolved as follows

  1. Too much wind
  2. Not as fast as I would have thought
  3. A lot of time and money went into this…
  4. It’s like an asphalt dune buggy
  5. This thing is actually kind of awesome

There are a lot of reasons for owning a sports car. I don’t think any of them are about how practical the cars are. In fact, some of their appeal is their lack of practicality. The main appeal of sports cars, in my opinion, is how they make you feel. That feeling should be special. And if you’re the kind of person whose mantra is “built not bought” then an Exocet is going to make you feel doubly special. I would never build an Exocet myself. I’m a driver, not a builder. Heck, I’m not even a sports car enthusiast. But there is a part of me that is 100% on board with what this represents.

Thanks Colin and Mike, the Exocet made my coaching day special.

You suck at luthiering?

I have a lot of hobbies. Possibly too many. While auto racing currently occupies the plurality of my attention, I have been obsessed with lots of things, many of which are sports: skateboarding, tennis, basketball, lacrosse, fencing, archery, marksmanship, soccer, biking, climbing, etc.. On the non-competitive, artistic side, I have writing, music, and programming. Sometimes hobbies collide and weird shit happens. For example, I wrote a novel about car racing. This was done as part of the National Novel Writing Month, which takes place every November. No, you can’t read it. It’s horrible. The point of NaNoWriMo is to draft a novel in 1 month, not write something publishable.

In another car-meets-art effort, I’ve begun to make some guitars from valve covers. I don’t know anyone whose done this before. I’m calling these Overdrive Guitars. I’ve built 5 so far. The first was a bass guitar made from a 1.8L Miata. While this worked okay for bass, it’s a little large for guitar. So I went to the local Pick-n-Pull to look for something more suitable. Ideally, the neck fits into the gap between the cam lobes, and the cover shouldn’t be too thick. After a couple hours in the scrapyard, I came away with several Honda B18 and B20 covers.

The first prototype I built featured a B18A1. These were found in non-VTEC Acura Integras from 1990-1993. This is the 3rd guitar in the image below. I didn’t do any cutting on the body, but milled the neck to fit the slightly narrower gap between the cam lobes. The neck is 25.5″ scale length and the electronics are a pair of P-90 soap bars with dog ear covers. The bridge is a typical tune-a-matic affair. I was going to strip all the paint off it and then give it a proper paint job. But then I thought I was ruining part of the authentic aesthetic and left it unfinished. It is a prototype after all.

The next 3 guitars feature a 24.75″ scale length, as you would find on Gibson guitars. The guitar on the far left is another B18A1, but this time the body has been extensively modified. There is now a proper horn and the neck cavity has been milled to fit the neck. The pickups are once again P-90s, but this time without covers. The bridge is an interesting wrap-around design.

The 2nd and 4th guitars are both made from B20A5 covers, which were sourced from Preludes. These also feature cutaways for access to the higher frets. The pickup is a solo humbucker. The 3-way switch is therefore an on/off switch rather than a pickup selector. The bridge allows for anchoring through the rear or with sockets (I chose the latter).

In addition to these mostly finished models, I also have a B18B1 (94-01 Integra) guitar I just started. Building these guitars takes more time than you might guess. There’s a lot of work in cutting, abrading, and drilling the aluminum, but the biggest pain is making sure everything aligns properly.

How do they sound? Aluminum has good acoustic properties, and everything is put together solidly, so they sound good. If I didn’t suck at guitar, I’d upload something to YouTube. Maybe I will anyway, but not today.

Are they for sale? Yes. I plan on keeping one, but I’ll sell the others to recoup my expenses (and maybe get supplies for the next batch).

Nannies: good or bad?

As a driving coach, I get to ride in a lot of cars. Most of them these days have really impressive nannies, by which I mean the combination of anti-lock brakes, traction and stability control. These systems are mandatory on all new cars today in the US and EU and have been for a few years. The reason for this is that nannies save lives. While expert drivers may be able to control a car more effectively without such gadgets, I’d guess that 99.99% of drivers are safer with them. Personally, I’m glad all new street cars have nannies.

As a driving enthusiast and performance driver, what do nannies mean to you?

  • Faster – except for truly advanced drivers, nannies will see you lapping faster.
  • Safer – you’re much less likely to drive off track, spin, or hit something with nannies on.
  • Cheaper – you can read the sensors through the CAN bus and save thousands of dollars on telemetry.
  • Dumber – you won’t know how to control a car that doesn’t have nannies.

In spirit, nannies aren’t much different from an automatic transmission. If you spend all of your time in a car with automatic transmission, you’ll never learn how to operate a clutch or gearbox. How important is shifting to the driving experience? I don’t know. I’ve raced with an automatic transmission and it still felt like racing. Most engines these days automatically advance the ignition timing. Engines didn’t always do that. Have I lost an essential skill of driving because I don’t manually advance timing? I generally don’t think so, but some curmudgeon somewhere probably does.

As a coach, I love getting into a modern car because I know I’m much safer. Even though modern cars have way too much power, they also have nannies to prevent the car from spinning off course. I’ve had several experiences where I thought, “well, this is going to suck” only to have the nannies simply change the shape of the corner and leave me thinking “great car”. I rarely get into such situations and think “great driver” because the driver was the problem, not the solution. However, when I get into a car without nannies and the driver recovers from a difficult situation, all I have is praise for a driver who is learning to “explore the space”.

As a learning tool, bicycle training wheels are both a blessing and a curse. They save a lot of scabbed knees and possibly broken bones. But they have a fundamental flaw. When you’re riding a bike, you steer by leaning. Training wheels prevent that. I feel the same way about nannies. They prevent oversteer. However, if you ever want to be able to control oversteer, you’re going to have to experience it. Eventually, the training wheels have to come off if you’re going to learn how to really drive a car.

That said, if you’re going to your first track day, please leave the nannies on. Consider taking them off on your 3rd track day. However, if the car is your daily driver and replacing it would be financially painful, don’t do it. Leave the nannies on to protect yourself and your investment. An older Miata or 3-series is an ideal way to get a nanny-free experience. And if you brick it, it’s not that big a deal.

Of course, you can also get a nanny-free experience driving in simulation. It seems like I talk about the merits of sim racing every week. Well, that’s because it’s such an inexpensive way to train.

You suck at dieting: part 2 of 2

Last week I talked about my general approach to dieting. This can be summed up pretty simply.

  1. Dieting is as simple as calories out > calories in.
  2. Using a scale and calorie counter to track weight loss is like using a stopwatch and telemetry for improving your driving.
  3. There is no need to get caught up in the composition of the food when it is the amount that matters.

This week I want to talk about some specific tips and tricks to help you lose weight.

Eat healthy foods

While dieting is more about the amount of food rather than the composition, when you’re restricting calories, you need to have a balanced diet to stay healthly. Eat nutritious foods. You know what they are without me enumerating specifics. In general, healthy foods spoil when you leave them out. Things that don’t spoil aren’t even food. If bacteria and mold can’t thrive on them, you can’t either. Drink water. If that’s too boring, add some lemon or lime to it. Alcohol contains a lot of calories and prevents you from metabolizing fat, so minimize alcohol consumption.

1 pound per week

While it’s possible to lose more than 1 pound per week, I don’t think it’s good for your body to stress it out too much. 1 pound per week amounts to a 500 calorie deficit each day. That’s enough of a difference to see progress without doing yourself any harm. Note that your weight fluctuates throughout the day depending how much food and liquid you have in your body. Don’t be discouraged if your weight goes up some days. When viewed over the course of weeks, it drops steadily.

The NOBLES diet

Last week I turned my nose up at diets, but I’m going to tell you about one I invented for myself: the NOBLES diet. NOBLES  is an acronym for NO Breakfast or Lunch Except Socially.  It’s a form of intermittent fasting. The diet has absolutely nothing to do with food composition or amounts, but rather when you eat: which is only at dinner. The reason to use this diet is not necessarily to lose weight, but rather to train yourself out of feeling hungry. Having long periods of time when you’re not allowed to eat will give you an opportunity to challenge your hunger feelings. The more you deny your hunger, the better you’ll get at it.

The Except Socially part of the NOBLES diet recognizes the fact that dieting is not the most important thing in your life. Eating with other people is sometimes critically important in business relationships. Don’t tank your career for vanity. If you have to eat breakfast or lunch with someone, do it, but then you might have to restrict what you eat for dinner or the next day. The Except part isn’t an exemption from dieting!

Dieting is supposed to be hard

One of the critical stages in improving your driving is getting comfortable being uncomfortable. That means taking corners at higher speed and driving with greater yaw. When you first start driving, you’re not comfortable sliding a car around, but that’s how a car is supposed to behave on track. The dieting equivalent is being satisfied with being unsatisfied. You have to get accustomed to hunger.

Dieting sucks, especially the first few weeks. You’re going to feel hungry all the time. You have a few hundred million years of animal evolution demanding that you eat whenever possible because historically food has been scarce. But your ancestors went long periods of time without eating and it didn’t kill them. You can make it through the day on 500 calories less. Poor people the world over do it all the time.

I’m morally opposed to things that are supposed to make dieting easier. Here, take this pill and you won’t have an appetite. Eat only ______ and you won’t feel hungry. One of the most important parts of dieting is you taking control of something that’s really difficult. It’s a mental challenge. It’s difficult, and it’s supposed to be. Don’t cheat yourself out of the experience by looking for shortcuts. Just like race prep, shortcuts end up being the long way around.

No days off

A couple days off can ruin a couple weeks of good dieting. Each day, you’re only missing 500 calories. It’s not a lot. It’s much easier to eat 500 more than 500 less. A weekend of binge eating and drinking could see you easily consuming an extra 2500 calories. That’s 2 days undoing 5. One reason dieting is so hard is that it takes commitment every single day.

One of the hardest things about dieting is convincing yourself that every little bit matters every day. Does every crumb matter? Actually no. But the attitude matters. The world is full of people doing shit half-assed, and it’s not better off because of it. When you get right down to it, dieting isn’t really that complicated. It’s just consuming less food. It doesn’t take a whole lot of mental or physical skill to diet, just willpower. Commit yourself for no other reason than you don’t want to be one of those people who coast through life doing shit half-assed.

A 10 minute mile is just as long as an 5 minute mile

Exercise is an important part of weight loss, but overdoing it will undo the good. This is especially true when you start a new exercise program. There’s a desire to jump in and work out like crazy. Pulling a muscle will set you back weeks. It’s like driving too hard on cold tires. Spinning could send you home early. Start gradually. Weight loss takes months. There’s no reason to rush in the first days or weeks. Incidentally, I don’t think I’ve ever been able to run a 5 minute mile. I’ve only been a timed a few times, but when I was in college in peak shape I barely broke 5:30.

Catch up on TV, movies, audiobooks, and podcasts

Exercise time is a great time for your media consumption. I listen to audiobooks at the gym (and elsewhere). As an aspiring author, I consume a lot of books to understand how people construct them. Back when my knees weren’t totally shot I used to work out with a stationary rower while watching movies on Netflix. It’s hard for me to watch movies sitting on a couch because I always feel guilty, like I’m supposed to be doing something else. Watching while exercising is therefore a useful synergy for me. This Summer, I’ve added swimming to my exercise regimen. I’m not a very efficient swimmer, and it’s a little frustrating. Yet another mountain to climb…

You suck at dieting? part 1 of 2

Dropping pounds is a lot like dropping seconds: conceptually simple, but difficult in practice. I consider myself an accomplished dieter. My weight cycles between 165-173 pounds (75-78.5 kilos). When it gets to 173, I purposefully lose weight until I’m 165. Then I forget about dieting until I hit 173 again. The cycle takes about 6 months. Why don’t I just maintain 169 or something? Because it bores me. I actually enjoy losing weight. It’s almost as fun as gaining weight. But losing weight is hard. Your body doesn’t want you to do it. Well, I like challenges.

As a college student, my weight was a steady 165. I was highly active in a variety of athletics and never considered what I ate. As a graduate student in my mid-20s, I maintained a slightly higher weight: 175. I was still very active (tennis mostly) and ate whatever I wanted whenever I wanted. I recall consuming a lot of pizza and soda. When my wife became pregnant, I gained a lot of sympathy weight. At my peak weight, I was about 190 pounds (86 kilos). Throughout my 30s and early 40s I maintained a weight of about 180-185 pounds (82-84 kilos). And then one day in my mid-40s I decided it was time to lose weight. I got down to 176 pretty easily, but that was a plateau I couldn’t break through until I changed my strategy. Eventually, I got down to 161. At that point a friend asked if I had health problems. I figured it was time to gain weight, and from then on my weight has been between 173 and 165.

This post and the next are about my approach to dieting. Shedding 10 pounds will make your car faster and use less consumables. So this is totally legit race talk even if it sounds like health talk.

The job of the racing driver is to find every tenth of a second to lap as quickly as possible. But the driver also has to do it safely. So it is with the dieter. The dieter must drop pounds as quickly as possible while staying within a safety margin. You should not attempt to drive on a race track unless you are physically fit enough to do so. And you should not attempt to diet unless you are in good health. I can’t stress this enough. You have absolutely no business losing weight if you’re ill. There’s an old saying “feed a fever, starve a cold”. FUCK THAT. Feed a fever and feed a cold. And feed every other malady while you’re at it. The best time to lose weight is when you’re 100% healthy. And then, at a pace that isn’t dangerous.

There are tons of diets that people have invented over the years. Popular diets today include Atkins, cleansing, ketogenic, paleo, raw foods, Slim Fast, South Beach, vegan, vegetarian, Weight Watchers, etc. I don’t do any of that complicated bullshit. I eat exactly the same kinds of foods whether I’m losing or gaining weight. It’s not about the type of food, but rather the amount. When you break it down, dieting is really simple. There is only 1 thing to consider.

  1. Calories out > calories in

The problem with some of the fad diets is that they are often a highly polarized balance of nutrients that help you lose weight by making you less healthy. You can lose weight with a high protein diet or a low protein diet, or a high carb diet or low car diet. None of these is a great idea if you ask me. Another class of diets is those where the inconvenience helps you lose weight. For example, on a rainbow diet, you’re only allowed to eat food that matches the color of the day (such as red on Mondays, orange on Tuesdays). You’re better off learning how to control your hunger rather than having some obscure rules control it for you.

How do you know if your lap times are improving? You time yourself. But that’s an overly simplistic answer. It’s more important to understand why your lap times get faster. What specific things does one do to drive closer to the limit? For that, you need to dissect your driving and understand the process of driving rather than just the result. Telemetry is essential. I use a RumbleStrip and Aim SoloDL. I also just got an APEX Pro, which I’ll review soon. Without the right tools it’s really hard to get faster.

Dieting without the right tools is similarly difficult. Fortunately, dieting tools don’t cost very much. All you need is a scale and a smartphone. The scale is like a stopwatch. It tells you if the results of your efforts are bearing fruit. Trying to lose weight without a scale is like trying to drive faster without a stopwatch. Simple bathroom scales are as little as $10. I have a $72 My Weigh SCMXL700T. This is totally unnecessary for weight loss, but since it has a 700 lb limit, I also use it to get corner weights on my racecars. If you do this, you’ll just need to make a set of 4 shims the same height as the scale (you’d think you only need 3 but it’s easier to swap things around with 4).

The dieting equivalent of an Aim SoloDL is a calorie counter. I use Lose It!, but there are many, many equivalent apps to choose from. Here’s a screenshot showing my weight chart over the last 5 years (everyone asks about the spike in the middle, which was a data entry error).

Don’t want to count calories? Well, that’s like wanting to drive faster but refusing to use telemetry. Good luck with that. Get over whatever the fuck your problem is and start counting calories. Understand the process not just the result. The reason you’re overweight may be simply because of your stubborn refusal to count calories. Remember, the only rule of dieting is calories out > calories in. Fad diets like to make dieting about food composition. Only drink liquids. Only eat raw foods. Avoid high fructose corn syrup. It’s not about the food composition, it’s about the calories. Eat normal healthy food, but less of it.

Sweeteners

To illustrate the misunderstandings of food composition, let me rant a bit about high fructose corn syrup (HFCS). This sweetener is used in canned sodas and other drinks. Lots of people look at the modern problems with obesity and diabetes and point to HFCS as the culprit. What exactly is HFCS? Table sugar is a mixture of 50% glucose and 50% fructose tied together in a single molecule called sucrose. HFCS is a blend of fructose and glucose, having more fructose than glucose, typically something like 55%/45%. The health-conscious world has 2 reasons to hate HFCS.

  1. Your body can detect changes in glucose but not fructose. HFCS therefore has more undetectable sugar, which leads to diabetes.
  2. HFCS is inherently bad for you because it is a processed food and unnatural. Better alternatives include honey and agave syrup.

The 10% difference in the balance of glucose and fructose is not going to give you diabetes. You could consume the exact same amount of fructose by simply not finishing the last bit of your drink. It’s the amount of sugar that’s the problem, not the balance of glucose and fructose. If it was the balance that’s the problem, you should also stay away from honey. It has the same ratios of glucose and fructose as HFCS. And what of agave syrup? That shit is 90% fructose. If you’re worried about fructose intake, it’s about the worst possible sweetener you could consume.

What about artificial sweeteners? Why the fuck would anyone want to fool their bodies into thinking they are consuming calories when they are not? That kind of shit never works out in the end. Stop making your diet about composition and start making it about amount. Want some sweetener in your coffee? Use actual sugar, be it sucrose, agave, or honey. And then record it in your calorie counter app.

Rev-mashing: part 2 of 2

Are you rev-matching or rev-mashing? Let’s repeat the question from the end of last week. Where in the corner should you downshift and what are the consequences of shifting at the wrong point.

Red Zone

Lots of people start to downshift during threshold braking. As soon as they hit the brakes, they also depress the clutch and blip the throttle. There are several problems with this.

  • The car was already at high RPM and the blip just sent it even higher.
  • The car is currently going too fast to engage the lower gear.
    • If you shift to the lower gear immediately, you may destroy the engine by revving it past redline.
    • If you wait with the clutch depressed, the engine and transmission will spin down, negating any benefit of blipping the throttle. When you do engage the clutch, you’ll have to feed it in gradually to prevent locking up the tires. Congrats, you just ruined your brake bias and made the stopping distance longer. You’re also putting wear on the clutch.

Blip-shifting in the red zone is the worst possible place to shift.

Orange Zone

This is generally the best place to downshift. For really long decreasing radius corners, it’s too early though, as you’re still aggressively bleeding speed through half the corner.

Yellow Zone

In this trail-braking zone, your concentration should be on controlling the speed and angle of the car using a combination of brake pedal and steering wheel. It’s not a good time to take your hand off the wheel or dance on pedals.

Green Zone

This is the point of maximum lateral g-force. Your foot is making the transition from brake to throttle. In longer corners with extended trail-braking zones, this is a fine time to shift.

Blue Zone

You’re balancing throttle and steering as you pass the apex and track out to the exit. The over-rotation you initiated in trail-braking has to be wound out some in here. Probably better to keep both hands on the wheel.

Purple Zone

Although it seems way too late, shifting in the Purple zone is an ok place to shift. You’re not going to break any lap records doing it this way, but you’re also not going to do any damage to the car. If you drive through a corner in a gear that’s too high, it’s not that big a deal. If you’re balancing throttle and steering, as you should be, you don’t really need full power anyway. I don’t know anyone who actually downshifts after a corner. It would be like shooting free-throws underhanded: works okay, but looks too silly to be taken seriously.

Demonstrations

Here’s a popular YouTube video instructing how to heel-toe shift. The video overlays footwork and RPMs. Watch as he starts the downshift too early. The revs drop and feeds out the clutch gradually. If you have to release the clutch gradually, you’re not rev-matching, you’re engine-braking (or engine-breaking). One wonders how such a flawed example can have so many views.

Here’s the right way to do it. Notice how quickly the clutch is released as he blips each gear. You might also notice how he changes his hand position depending on which gear he’s selecting. It’s most noticeable for 2nd gear where he rotates his hand thumb-down. He’s not doing this to look cool, but I’m guessing somewhere there’s a ricer in a stanced Honda back-handing every fucking gear…