Last week I posted about the Lucky Dog sim racing series I attended. In the post-race FB chat, I offered to help a slower driver get faster if they were willing to look at telemetry with me and didn’t mind me blogging about it. The only person who took me up on that offer was actually one of the faster racers. The next race on the schedule was Summit Point, so that’s what we would work on. I haven’t run Summit in ages and I’ve never driven the ND MX-5 there. Sometimes I wonder why I keep an iRacing subscription. My laps wouldn’t be ideal, but I logged a couple sessions to get some telemetry for comparison. One expected difference is our setups. He downloads setups from aliens whereas I drive the baseline like a rookie. Setups are critical when looking for tenths of second, but not 1.6 seconds, which was the gap between my fast lap and his. My goals were (1) to figure out why he was 1.6 seconds off and (2) to see if I could offer some advice that would help him get faster. In a perfect world, I’m such a good teacher that he ends up faster than me. I can dream.
The “student” has done some racing in the real world and has been on iRacing for a little over a year. Good, that means we could dive right into the data without troubleshooting rookie problems like how to set up controllers or drive the typical racing line. In the telemetry traces below, you can see panels for Brake, Speed, Steering Angle, Throttle Position, and Time Lost. iRacing reports over 100 channels, but you don’t need more than 4-6 to figure out what’s going on. The image is a screen capture from TrackAttack. One of the things I like about TrackAttack is that it is available on PC and Mac, imports a variety of data formats (e.g. iRacing, AiM, Apex Pro), and stores its data on the cloud. Viewing and sharing telemetry data has never been so convenient. Click on the image to view it full size.
The student trace is yellow and mine is purple. Let’s look at the obvious things first: brake and throttle.
- He brakes a little later and a lot harder than I do
- He gets to 100% throttle sooner than I do
In a lot of peoples’ minds, the formula for speed is braking as late and hard as possible followed by accelerating as early and hard as possible. But if that worked, why are my speeds higher pretty much everywhere on track? It’s certainly not the setup. Given that I’m using the baseline and haven’t even bothered to move some weight to the right side of the vehicle, he should carry more speed in the right hand corners, which is most of them. The clue to this mystery comes from the steering angle: he turns the wheel more than me. So when we struck up a FB Messenger conversation, that’s where I started the dialog.
I looked at your traces… the more you turn the wheel, the more speed you scrub. How does one get around a corner without steering as much?
Better racing lines. Lol.
No, it’s not the line.
(At this point I sent him a TrackAttack screen cap showing the steering angle trace).
Wow! Minimizes the sudden weight transfer by being smoother and only turning as much as necessary….
We both have to turn the same amount at the end of the day. My car is turning just as much as yours believe it or not. The difference is that I’m not using the wheel to do it.
Ahhhhhh….gotcha. Skinny pedal. Lol.
Earlier brake? Or trail brake?
Yeah and yeah.
Both. Roger that.
Your current style is to brake late and hard. When you do that, you can’t rotate the car.
Little earlier on, later off, but less overall pressure.
Earlier on, less pressure, earlier off actually. You can move the whole braking sequence earlier in the corner and carry more speed through the corner.
Oh gotcha. Makes sense. That’s probably why I struggle with a real car that way as well…
The harder and later you brake, the less time there is to set up the ideal corner speed. The less time there is to feel the balance of the car. There’s nothing wrong with threshold braking. But it takes away your time to sense speed. So until your speed sensing skills are exquisite, it’s better to give yourself more time at the corner entry to find the optimal entry speed. I brake pretty softly in real and sim life. I haven’t figured out how to threshold brake and sense speed.
I see. So by braking earlier, you can rely more on the momentum of the car and the suspension instead of sending it in hot and praying that the tires can soak up the forces.
Braking too hard will also see you below the optimal corner speed. The natural reaction to that is to stomp on the throttle. But if you do that, all the weight goes to the rear and the front starts understeering. So if you find yourself pushing, it’s probably because you’re also using a lot of throttle. And that’s because your corner speed was too low.
Got it. That’s exactly what I feel like I am doing, too….
So next time try braking a half marker earlier and trail off the speed to keep as much momentum as possible. It takes a while to change driving style. Don’t expect miracles. Things get worse before they get better sometimes.
The student knows a lot about driving and is a pretty fast driver. It’s great that we can have a conversation about racing line, weight transfer, understeer, etc. without having to define terms. What’s holding him back are some misconceptions about the fast way around a track. He’s probably had these misconceptions for a while and has a driving style that optimizes them. In order to get faster, he’ll have to unlearn some of what he currently knows and re-train himself to drive differently. Let’s talk about his misconceptions in a little more detail because everyone goes through this.
- Brake as late and hard as possible
- Get to 100% throttle as soon as possible
- Oversteer is generated via the throttle pedal
On the surface, all of these are correct in their own context. If you’re trying to get as much out of the straight as possible, you should brake as late as possible. And if you’re trying to slow the car, you should be using all the traction you have available, not part of it. The reason we drive the typical racing line is to maximize the exit speed. So it makes sense that you want to get on throttle as soon as possible. It’s also true that you can initiate and control oversteer with the throttle. So if all of these things are right, what’s wrong?
I think there are 3 phrases in common usage that improve the novice driver and shackle the advanced.
- In slow out fast
- You should always be on throttle or brake, never coasting
- Whoever gets to 100% throttle first wins
All of these phrases emphasize the speed of the vehicle. By any objective criteria, I’m doing the speed things worse than the student. I brake softly. I’m late to brake and throttle. I coast. What am I doing right that makes up for all that I’m doing wrong?
- The winning driver is the driver who turns less
So how does one get around a race track by turning less? It starts by learning how to control oversteer with the brake pedal. That’s it. Just one little thing. The brake pedal. And fuck all if I’m not still working on it.
One thought on “Coaching Report (-ish)”
Thank you! I was fortunate enough to have some time with a great instructor and one of the things that he’d mentioned is that, depending on the track, he threshold brakes in 0-2 corners. He was good enough (both objectively as a driver and subjectively as an instructor) that I believed him, but I never really understood *why* he’d “leave braking power on the table”. Your explanation makes perfect sense.