Achilles Update: Crisis = Opportunity

I just had surgery on my Achilles. It was torn up pretty bad, and they used someone else’s to put me back together. So now I’m a bit like my Yaris with Corolla brakes. Or my Z3 with E46 brakes. Or maybe part zombie?

It’s going to be a long recovery. I’m supposed to stay 2 weeks at home and then they’ll take the stitches out and slap a cast on me for 2 weeks. After that I’ll be in a walking boot and start physical therapy. The recovery is about 1 year.

Crisis represents opportunity. Let me tell you about 2 opportunities.


Some of my favorite high school memories are playing pool over at Dan’s house. Later, in college, when my parents moved to NYC for a year, we took over their house and installed a pool table. Since then, I’ve always wanted to have a pool table but never had the opportunity. Knowing that I was going to be out of commission for a while, I rearranged my garage and storage shed to accommodate a pool table. I can’t wait until I’m well enough to play. I’m thinking about ways to track my progress as I improve. If you have any ideas, let me know.

Left Footed Driving

I’ve never felt the need to learn left foot braking. The few times I’ve done it (kart or F1 sim rig), it didn’t feel terrible, just awkward. Now that my right leg is out of commission for a while, I’m thinking about left foot driving. Not for HPDE or racing, but just to get to work. My plan is to learn this on my sim rig by swapping the inputs in software. I’ll probably change the spring in the pedal too, as the clutch is kind of heavy.

There are plenty of left foot accelerator pedals on the market. Some of them are bolted into the car, and some are portable. I’m not sure which one I’ll get. Commuting to work is about to get a lot more interesting. These only work with automatic transmissions, so the Z3 is going to be lonely for a while.

In slow, out fast, and other lies of the racetrack: part 4 of 6

6 Big Lies

We’re half way through 2022 in the middle of the racing season. Seems like now is a good time to talk about some of the stupid shit people say in the guise of offering helpful advice.

  1. Drive the racing line
  2. In slow, out fast
  3. The first driver to full throttle wins
  4. You should be on throttle or on brake, never coasting
  5. Imagine a string connecting your steering wheel and throttle pedal
  6. Separate braking and steering

Always on brake or throttle

I’m sure you’ve read that you’re supposed to always be on brake or throttle, and that coasting is a no-no. But I don’t subscribe to this at all. In fact, I think that coasting is very important. First off, why do people say you shouldn’t coast? I think it’s because novices coast too much. They coast at the end of braking zones. They wait to add throttle in a corner. Excessive coasting is a waste of time, literally, so instructors counteract that by telling novices not to coast. Does coasting make them slower? Yes. Does speed matter at the novice level? No. So who cares if they coast? I certainly don’t. What does matter at the novice level? Safety and fun. Telling novice drivers to be on brake or throttle all the time may make them feel uncomfortable, which results in less safety and less fun. Let them coast. They will get over it eventually.

YSAR isn’t really concerned with the complete novice. The focus of this blog is more on the intermediate driver. And the problem with intermediates isn’t that they coast too much, it’s that they coast too little. The typical intermediate driver has the following pattern of inputs.

  1. Mash the throttle
  2. Mash the brake
  3. Go back to step 1


Last time I talked about the importance of maintenance throttle and corner entry speed. So how do you enter the corner on the limit? Mark Donohue says “exiting a corner on the limit is like walking a tightrope, entering is like jumping on a tightrope blindfolded.” I disagree. Trail-braking helps you feel your way into a corner. The self-centering tug on the steering wheel is an indication of how much grip and speed you have. As you let off that last smidge of brake and are coasting, the car is still decelerating while it turns into the corner. Coasting while turning is a soft form of trail-braking. By modulating how long you coast, you can set your entry speed exactly how you like.

Take a look at this ancient diagram from Piero Taruffi’s classic “The Technique of Motor Racing”. Back in the old days, people didn’t trail-brake as much as today partly because tires were different. Look at segment 2. Braking is done, steering has begun, and the throttle is off. Coasting, deceleration, and turning! That’s the soft form of trail-braking I’m talking about. I’ll call it trail-coasting for lack of a better term.

For optimal corner entry speed, your suspension must not be rocking fore-aft or side-to-side. You want the ultimate balance of speed and grip, and that comes with having the car stable. Trail-coasting helps keep the car quiet. It also adds confidence. Without any focus on your feet, you can focus more on the feel of the car. A little coasting will give you the confidence to enter corners at a higher speed. If you go in too fast, coast a little more. If you enter too slow, coast a little less.

If you want to get better at using coasting to your advantage, you need to practice. My favorite track for this is Lime Rock. T1 is a long, decreasing radius corner that requires a lot of patience through trail-braking and coasting. The other corners are all coasting corners if you’re in a low power car. Here are my favorite training cars for Lime Rock in the virtual world.

  • rFactor 2: Skip Barber
  • Assetto Corsa: Formula Ford or Skip Barber
  • iRacing: Formula Vee or Skip Barber

If you’re training in the real world, try to pick just one or two corners per lap. Medium speed corners are best.

In slow, out fast, and other lies of the racetrack: part 3 of 6

Sorry it’s been a while since I last posted. My injury has me feeling sorry for myself and I haven’t been motivated to write about cars since I haven’t and won’t be driving them in a sporting manner for some time.

6 Big Lies

We’re taking a deep dive into stupid driving clichés.

  1. Drive the racing line
  2. In slow, out fast 
  3. The first driver to full throttle wins
  4. You should be on throttle or on brake, never coasting
  5. Imagine a string connecting your steering wheel and throttle pedal
  6. Separate braking and steering

Full throttle!

All else being equal, the first driver to full throttle wins

— some racing authority

The problem with this statement is that it gives one the idea that full throttle is an important goal. If you want to spend a lot of time at full throttle, stop the car in the corner, and drive out of the big hole you created. Clearly, that’s not a great idea.

One of Ross Bentley’s favorite coaching exercises is that he asks students to estimate how much of the track they are at full throttle. If the student says 65%, he says try 67%. I think this can be a good exercise, but again, the emphasis is on full throttle, which I don’t really like.

Zero steer

Let me tell you one of my secrets: the key to driving faster isn’t full throttle, it’s maintenance throttle. When does maintenance throttle happen? In the middle of the corner. From the time you let off the brake to the time you’ve wound the steering all the way out, you’re on some form of maintenance throttle, not full throttle.

If you’re full throttle in the middle of the corner, you didn’t go in fast enough


There isn’t much nuance to full throttle. That’s why it doesn’t separate bad and good drivers. Anyone can mash a throttle pedal. When you’re in a 4 wheel drift, which Paul F. Gerrard calls “zero steer”, you change direction with the throttle pedal. More throttle: increase radius. Less throttle: decrease radius. If you’re steering the car primarily with the steering wheel, you’re not in zero steer. You’re not at the limit. You went in too slow.

Driving the limit

If you want to get a lot faster, don’t focus on how much time you’re on full throttle. Instead, focus on how much time you’re forced to be at maintenance throttle because you couldn’t go any faster without falling off the track. Exit speed is determined by mid-corner speed. Mid-corner speed is determined by entry speed. If you’re not at the limit on the entry, you won’t be at the limit at the exit.

How do you know if you’re at the limit through the corner? Data of course. You need to compare your data traces to faster drivers. Where do you get that data? I don’t really know in the real world. But it’s easy to get in the sim racing world. As an added bonus, you can make sure that the people you’re comparing to are using the exact same car with the exact same setup and weather.

That said, you can’t rely too much on data. Ultimately, you drive the car by feel. You have to figure out what it feels like to drive the limit. More importantly, you have to figure out how it feels to be OVER the limit and then still be able to navigate your way through without crashing. This is why I say that the only thing better than driving the limit is a brief trespass and safe return from well beyond. Trusting your skills to save you feels even better than executing the perfect corner.

So the big question is, “does sim racing make you faster at cornering in the real world?” YES, it definitely worked for me. I’ve driven less than 100 hours on track in real life, and only a couple hours in the rain. Yet my rain corner speeds are much faster than other people I race against.

How do you learn to enter a corner on the limit if you don’t have a sim rig? I don’t really know. But if this is your plan, take your time and don’t do something you’ll regret later.


In slow, out fast, and other lies of the racetrack: part 2 of 6

6 Big Lies

If you’re just joining us, we’re taking a deep dive into stupid driving clichés.

  1. Drive the racing line
  2. In slow, out fast
  3. The first driver to full throttle wins
  4. You should be on throttle or on brake, never coasting
  5. Imagine a string connecting your steering wheel and throttle pedal
  6. Separate braking and steering

2. In slow, out fast

As a driving student, you have surely heard the phrase “in slow, out fast”. This may have given you the idea that you’re supposed to brake heavily before a corner and then hammer the throttle on the way out. You’re not. The reason faster drivers tell slower drivers “in slow, out fast” is because faster drivers want to continue to be faster than you. Racers have fragile egos and they don’t need more competition.

Wait, is that really true? Yes, everything on YSAR is 100% true all the time.

Let me tell you what the fast racers won’t. Every corner has an ideal entry speed. Your job is to match that  speed exactly. Not 1 mph slower or faster. If you end up below the speed, bad things happen. If you go over the speed, different bad things happen. What separates fast drivers from slow drivers is how close they get to the ideal entry speed. And what separates safe drivers from dangerous drivers is their ability to handle going over the ideal entry speed.

Most improving drivers have no idea what the ideal entry speed is or how to feel it from inside the car. The consequences for going in too fast can be crashy, so many drivers tend to enter well below the limit. Let’s see what that looks like.

Data or it didn’t happen

The picture below is the first speed graph I ever posted on this blog. It represents two drivers in the same car (Miata) at the same track (Willow Springs) on the same day. The blue trace is me and the red trace is another driver on my team. 

Look at the red trace in T1. This is a typical in slow, out fast corner. If you didn’t have the blue trace, you may think that the red driver is doing okay. However, in comparison, it’s obvious he’s way off pace. This is why you must record data and compare yourself to other drivers. If you’re not logging data, you’re not taking driving seriously. And if you’re not comparing data, you’re not taking learning seriously. If you’re serious about wanting to improve your driving, keep reading YSAR. If not, you might as well stop now and do something more entertaining, like driving your car under the limit.

In slow, out last

Where were we? Ah yes, what happens when you over-slow the car? Nothing. So what’s your response? Out fast, of course. Isn’t that where the fun is? You can see from the steep upward slope of the red line, that the red driver gets on throttle more aggressively than the blue driver. This is a direct result of “in slow”. If you enter a corner well below the maximum entry speed, you are invited to add a lot of throttle. What happens next isn’t good.

  • Adding throttle moves weight and grip to the rear. In other words, grip is removed from the front, which is called understeer.
  • Mid-corner understeer often leads to running wide at the exit.
  • Running wide to the exit may mean going off track. Inexperienced drivers who go off track sometimes turn a lot when the wheel goes light and end up crossing the track to the inside. Lots of wrecks are caused by dropping a wheel at the outside and hitting the k-wall on the inside.
  • An alternative to running wide at the exit is lifting at the exit. So, just when you should be going to full throttle, you’re having to lift to prevent yourself from going off track. That’s slow.
  • Adding throttle in a corner can also lead to oversteer in a RWD car. While this may look cool, but drifting has lower grip than not drifting. In other words, mid and late corner oversteer is slow.

To summarize, entering a corner well below the limit doesn’t just make you slower in the early part of a corner, it also makes you slow later as you battle understeer or oversteer. This is why “in slow, out fast” is actually “in slow, out last”.

In on the limit, out on the limit

So why do we tell driving students “in slow, out fast” rather than something like “in on the limit, out on the limit”? Safety. It’s a clever way of saying “please survive the weekend” without actually saying “please survive the weekend”. Unfortunately “in slow, out fast” is so easily remembered that drivers take this lesson with them beyond the novice stage.


Here at YSAR I’m not going to bullshit you. I’m not selling anything. If you want to learn how to hit a tennis serve correctly, you will hit a lot of balls out of the court. Similarly, if you want to learn how to drive a corner at the limit, you will sometimes go off track or spin. This is what learning looks like in a high performance driving setting. If you do your learning in a safe practice environment (e.g. sim racing, skid pad), your crashes may not be costly. However, if you attempt to learn car control skills in a real car on real race tracks or streets, bad shit will happen to you. Don’t be a fucking idiot.

I suck at aging

I’m currently visiting family in Ithaca, New York. I thought it would be a good idea to get some exercise while here. Normally I bike to work as part of my exercise, but not having that, I thought I would turn to skateboarding. It turns out that was a bad idea. I was pushing the board to get some speed and my Achilles/calf popped. There was no warning. One second I was riding, and the next my leg was hanging behind me with my foot at an odd angle.

A couple of the people there helped me get back to my car. I found I had enough mobility that I could drive. It was painful and weak, and probably a little unsafe, but I drove myself to the emergency room. My mother has a handicapped placard, so I was able to park right in front. I hobbled toward the entrance and a kind woman fetched me a wheelchair. A minute later, she was bringing in her husband in another wheelchair.

I checked into their triage and then admitted to a bed where they did a few tests on me. They put a splint on me, gave me crutches, and a referral to see an orthopedic surgeon. I hobbled to the car and made it home. The entire ordeal from leaving the house, driving to the skateboard park, to getting injured, to getting medical attention, to arriving home, took a total of 90 minutes. I find that kind of amazing.

It’s been a couple days since the injury. It’s not as painful as I thought it would be. I guess there aren’t that many nerves down there. Also, I think the Achilles is only partially torn. I don’t think I’ll need surgery. I’ve been doing some mobility-based rehab to keep the blood flow high, and working with a theraband makes it feel better.

While this isn’t any fun, I’ve had much worse injuries in my life. This is a painful reminder that I’m getting older, and I need to do a better job of taking care of this body.

Big lies of the racetrack: part 1 of 6

6 Big Lies

We’re half way through 2022, and in the middle of the racing season. Seems like now is a good time to talk about some of the stupid shit people say to novices and intermediates in the guise of offering helpful advice. I’m sure you’ve heard some, if not all of the phrases below, and sometimes from highly reputable sources. But these weren’t meant to be laws. They were just introductions to the topic. In this series of posts I want to dig deeper into each of these “helpful” lessons and show why they can be bad advice.

  1. Drive the racing line
  2. In slow, out fast
  3. The first driver to full throttle wins
  4. You should be on throttle or on brake, never coasting
  5. Imagine a string connecting your steering wheel and throttle pedal
  6. Separate braking and steering

Drive the racing line

Every introductory book gives a description of the racing line. The geometric line is the outside-inside-outside line that gives you the maximum circular radius through a corner. This is in slight contrast to the racing line which has a later apex. Here’s a picture of the racing line from before I was born (and I’m 55).

One good way to think about the racing line is that it’s made up of 2 circular radii, the first one has a tighter radius than the second. This means you do more turning in the first half of the corner and more accelerating in the second half.

So what’s wrong with the advice to “drive the racing line?” I see two problems.

  1. Safety – the racing line puts you as close to the edge of the track as possible. It’s not the safest place for a novice to be.
  2. Intent vs. Result – the racing line shouldn’t be something you intend to drive, but the result of having the correct inputs.

I’ve heard some coaches say that one reason to drive the line is that it serves a kind of check-out role. That is, if a student can’t drive the line, they aren’t ready to go on to the next stage, whatever that is. That’s a pretty low bar. If you can’t drive outside-inside-outside around a track, you probably also have problems changing lanes on the highway or parallel parking.

What’s your line?

What’s your line through Turn X? This is probably the most common conversation at the race track. Drivers ask and answer this with such interest and passion that you’d think that this was the most important part of driving. Well, it isn’t. Any driver worth their weight in clag can find a decent racing line. The racing line is generally not what separates fast and slow drivers. What does is mostly competence, but also confidence.

Let’s take a look at the racing line as drawn from above, since that’s the way it’s usually discussed. Here are two drivers going around the same turn in the exact same car, on the same day, in the same hour. The direction is anti-clockwise (Thunderhill T2 in case you’re wondering). Which driver do you think is going faster?

It’s kind of hard to determine the faster driver from the racing line. They both enter the corner very similarly but they have different ideas about how to do the middle and exit. What do you imagine the speed difference is here? One mph? Maybe two? I know, let’s look at a speed graph because it’s a hell of a lot more useful than an overview of the racing line.

10 MPH

The difference between the blue driver and the red driver is about 10 mph. TEN MILES PER HOUR! Do you think that by adopting the blue driver’s line the red driver will suddenly be 10 mph faster? No. Driving on the racing line doesn’t mean you’re driving anywhere near the limit. Each point along the racing line has several dimensions in addition to the longitude and latitude, such as speed and yaw. If you’re positioned on the line but not at the right speed or yaw, you’re not really driving the racing line.

The reason these two drivers are at such different speeds has nothing to do with the line. So stop asking about it. It doesn’t fucking matter.

The question you should be asking

So if you’re not supposed to ask about the racing line, what are you supposed to ask? Ask yourself how close am I to the maximum corner speed? If you can’t answer this question with actual data, there’s no point in giving an answer because your feelings don’t mean shit. The only way to get an answer is to do both of the following:

  • Record data
  • Compare data

Recording data is easy. Your smart phone will work just fine. Even at 1 Hz, it will do an okay job of recording your minimum corner speed. However, just because a smart phone will work, doesn’t mean you shouldn’t get a better product. Dedicated devices like an AiM Solo are great, but I have to say that the Racebox Mini I just bought is more convenient, cheaper, and has a higher sampling rate.

The second part is harder. Where do you find data to compare yourself? Ideally, you’re using Track Attack, Race Studio Analysis, or something similar and you have some friends who also record data. But maybe you aren’t using these or don’t have friends to compare to. You can still make comparisons via YouTube. Find someone on similar tires and examine their corner speeds.

Another way to determine if you’re close to the limit is to examine your corner Gs. This requires knowing something about the friction of your tires. If you like math, you can measure the corner radius and then calculate the theoretical maximum corner speed. This too requires knowing the Gs of your tires. For 200TW tires, you can usually get a little over 1.0g.

Wrapping up

There are a few times when it’s normal to talk about the racing line:

  • Novice driver who doesn’t know anything
  • First time at an unfamiliar track
  • You’re searching for another tenth of a second

But most of the time, talk about the line would be better used to talk about just about anything else. Here are some ideas of alternative topics:

  • Reference points
  • Corner stations
  • Tire pressures and temperatures
  • Brake compounds
  • Sim racing
  • Weather
  • Dinner plans
  • Disapproving rabbits

More post-race thoughts

Let’s take a look at some more observations from the last race.

Daniel & David

Two of my drivers in the last race, Daniel and David, have been out of racing for a couple years. Neither of them has much time in the Yaris. So they took a little while to get warmed up. Their average lap times dropped by 10 seconds overnight. They didn’t drive off track or get into any trouble.

  • 4:17 Daniel Saturday
  • 4:07 Daniel Sunday (3:57 fastest)
  • 4:21 David Saturday
  • 4:10 David Sunday (4:01 fastest)


Tiernan drove the first stint of the race, which is usually slowest as there are cars and drivers that get weeded out later. His improvement from one day to the next was 22 seconds. Tiernan hasn’t been racing that long, and he’s now at the point where he’s getting more confident dicing with other cars. In other words, he’s at the dangerous stage of driver development. He stayed out of the penalty box both days, although he probably should have been flagged on Saturday for contact. Averaging 3:59 through traffic in a Yaris is pretty good, and a 3:52 fast lap is respectable.

  • 4:21 Tiernan Saturday
  • 3:59 Tiernan Sunday (3:52 fastest)

Mike & Danny

Mike and Danny are both confident and fast. They also tend to pick up a black flag every race, and this was no exception. Danny got black flags both days, which turned his 2:54 and 2:50 average pace into 4:03 and 4:04 lap times. Mike had a black flag on Saturday but not Sunday, and this turned into a 20 second difference in lap times.

  • 4:03 Danny Saturday
  • 4:04 Danny Sunday (3:44 fastest)
  • 4:15 Mike Saturday
  • 3:55 Mike Sunday (3:45 fastest)

Black Flags

Black flags are very costly. Over the course of a stint, they can add 10-15 seconds to your average lap time. Mike and Danny are consistently fast drivers, capable of putting down 3:45 laps. But if you average up all lap their times, their pace is only 4:07 and 4:08. In addition to loss of laps, each time you show up in the penalty box, you lose favor with the judges. If we ever want to win one of these things, we’re going to have to run a clean race from start to finish.

Fun vs. Winning

My team has a lot of fun on track. We chase down BMWs with twice our power. We pass Miatas on the outside of corners. We dominate in the rain. We also tend to have a bit too much internal competition. Mike & Danny like to compare lap times. To be perfectly honest, I like comparing lap times. I like pushing myself, and I like being the fastest. But that kind of attitude doesn’t win endurance races. The really good teams stay out of trouble, they don’t make trouble. WE MAKE TROUBLE.

Is it more fun to race safe and win or race fast and fail? Don’t ask me, I don’t know what winning feels like.

Race Weekend

I’ll update this post with things as they happen.


My race preparations are pretty streamlined at this point. It takes about 12 minutes to pack up everything I need for the weekend.

I arrived at the track to find that Lemons HQ is now under the far awning. So I’m parked right across from the main building. That’s pretty convenient for bathrooms and such.


It was an unseasonably cool day with a light breeze. Perfect for sitting around and doing mostly nothing.

We got the car inspected in just a couple minutes and got classed in C with 0 penalty laps. We’re pitted next to a 90s Accord with the C0 classification on one side and a Jeep-themed Miata on the other side that probably got B class despite being a little slower.

As the day wore on, we decided to inspect the brakes. I use StopTech 309 brake pads, which have the annoying feature of being good for about 20 hours. A Lemons race lasts about 15 hours, so I have a lot of pads with about 5 hours left. The mizer in me can’t throw away $50 brake pads, so I have a whole bunch of them. We picked through to find the best ones and decided we would use those Saturday and then do a full pads & rotors job between race days.

Towards the end of the day, Jason Simms, the Jeepiata owner, asked if I wanted to take a few laps in his car to give some driver feedback. Jason is the owner of Argonaut Garage in Berkeley, so he knows some shit about cars, but he’s not as confident about the driving part. I wasn’t planning on doing any driving, but I had my gear in case I was going to help fuel. So I got in the car and drove it 3 laps. The out lap starting from the pits was a 3:57, which was apparently faster than anyone did last year. I dropped it down to 3:53 on the second lap, and then brought it in. 3-ish laps was enough to get a feel for the car. It was typical Miata goodness. The only odd thing is that they had de-powered the brakes. I’ve never been in a car without power brakes and I can tell you that the first time I went for the pedal it was a bit of a surprise. I got used to it eventually, and I found it a really fun experience. There’s a lot more feel on brake release. However, if I had to stop in a panic situation, it would be a panic situation. Compared to the Yaris, the handling is better, but the acceleration might not be as good. It’s too bad we weren’t logging data.


It wasn’t the best day. The first driver got in a tangle and and suffered damage on the front left. The second driver went to the home pit instead of the hot pit, which burned a lap. The 4th and 5th drivers got black flags. And so we ended the day in 4th position, 4 laps behind the leader in class. If not for our own incompetence, we would be vying for first. But of course, that’s always the case.

After the race, we did pads and rotors. The only other maintenance we needed to do was to repair the front quarter panel.


We started the day with some body repairs and got on track on time. Despite clean driving all day, we ended up 3rd in class and P21 overall. Not bad. I have video to watch and edit, but it will be a few days before I can get to it. Check back for that.

How could we have won? Honestly, it would have been hard this race. We ran 5 drivers through the car every day when a smart team would have run 4 the first day and 3 the second. We also had a few mishaps as explained earlier. Overall, it was a good performance from the team and a great way to hang out with friends.


How well did RATTY work? It worked fine until the shifter became loose and cut the wire. I have to figure out a different placement for the button. Also, it would be better if there was more than one button. But it was nice being able to check in on the driver. Even when the button wasn’t working, we could still send text messages to the car.

Race countdown… 1

1 week from now we’ll be in the middle of a race. The weather outlook is sunny with highs around 88F. Not everyone likes wearing a coolshirt, but I certainly would be if I was driving. Let’s take a look around the interior.

I changed the Lithium battery in the front to a lead-acid in the rear. The battery box is a kitty litter container strapped to the floor. I got approval for this from JP, the tech chief. It’s just there in case of an acid splash. The battery is actually held down by a hefty aluminum bar.

Inside the cockpit, the biggest change is the addition of RATTY. The shifter has a button in the top. The base screws into the stock shifter threads. Yes, I tapped both the button and shifter. The metal in the base wasn’t as thick as I would have liked, so there’s a nut internally that screws in from the top. I didn’t have a very tidy solution for the wiring coming out of the shifter knob, so there’s some tape around it.

You can see the DIY cold box in the background. This is simply a marine bilge pump sitting in a standard cooler. The tubing and wiring come out of the top. It takes about 5 minutes to make one of these since the only thing you need to do is put a couple holes in the top.

The brains of RATTY (Arduino) are in a black box fixed to the base of the passenger seat with a hose clamp. There are 2 wires coming out of this, one for the shifter button (black), and one for USB power (white).

RATTY talks to my old iPhone 6S Plus via WiFi. Depending on how you press the button, it sends canned messages to a Discord channel. It takes 3-5 seconds for a button click to show up in the channel.

  • 1 click – Yes
  • 2 clicks – No
  • Many clicks – Bad shit has happened
  • Hold – I need to talk

The idea is that the pit and spotters can send status messages to the driver such as “Yellow in T2” or ask questions such as “is everything okay?”. The driver then responds mostly with yes/no answers.

In the picture above, you can see several devices in view.

Just to the left of the red stripe on the steering wheel is a RumbleStrip lap timer. Despite much fancier stuff on the market, this is still my favorite delta timer.

The stock gauge cluster is above the RumbleStrip. We don’t use it for anything other than the warning lights. The speedo doesn’t have a needle, and it isn’t missed since the RumbleStrip displays current speed.

To the left of the RumbleStrip is the tach. The car didn’t come with one, and honestly doesn’t need one. There’s no reason not to run it right to the rev limiter. It’s pretty conservative.

The rectangular screen to the left of the tach is an UltraGuage. This is an OBDII reader that displays up to 8 different things at a time. We use it to track engine temperature, stint time, and fuel usage. It works very well and is not expensive.

The car is also outfitted with a radio. I have spare NASA and IMSA headsets as well as adapters. I haven’t had great experiences with radios, but having redundancy is always a good idea. The radio mounts to the rectangular aluminum bar to the lower left of the UltraGauge.

The iPhone mounts on the far left. It gets fed power from a USB port on the passenger side of the car. Speaking of power, there are 2 12V outlets as well as 4 USB ports (half in front and half in back). The USBs power the iPhone, RATTY, and 2 cameras. The 12V outlets are not used, but exist in case we need to power something else (in the past this has been a Raspberry Pi and a monitor). The UltraGauge is fed power through OBDII and the RumbleStrip and tach are powered directly from 12V.