Speed Secrets: Coaching With Data
How to use data to coach yourself.
In the process of preparing for the Self-Coaching Masterclass that I’m putting on this week (https://speedsecrets.com/self-coaching-masterclass/ – registration closes tonight at midnight), I wanted to include a copy of an article I wrote a few years ago about how to use data to coach yourself. And in the process of doing that, I thought I’d share most of it here, as well. Let’s dig in.
Let me share a coaching story with you, one that took place at Watkins Glen. It will demonstrate how I used one lap's data to come up with just two strategies for improving a driver's lap times. The car being driven was a slightly modified production car, and it was during a track day, not a race. The driver had been high-performance driving for a long time, and was considered an advanced, fast driver; he'd been turning consistent laps at the Glen for years, but had plateaued.
I use this example to show you how you can use data to come up with a simple plan for your next track session which can lead to significant improvements. The data I used was simple: a Speed trace, although I did also have Lateral and Longitudinal g traces (they reinforced what I noticed in the Speed trace).
Watkins Glen is one of the most fun and challenging circuits in the world. Because it’s 3.4 miles in length, just a few small changes in driving technique can result in a big improvement in lap time. In fact, in the example I’m sharing here, just two changes led to a gain that many drivers would trade a body part for!
Below is a graph showing the Speed trace (upper line), Lateral g (middle), and Longitudinal g (bottom).
When I looked at this, I immediately noticed two things:
The areas circled in green hinted at a slow rate of acceleration and/or a large adjustment in speed, which suggested a lack of commitment to full throttle. The first green circle (looking from left to right) shows that the acceleration at the end of the front straight flattens out. That made me think the driver probably eased off the throttle well before beginning to brake. The second green circle is when the car is heading up the hill through the Esses, and the trace suggested that the acceleration rate should have been steeper, possibly meaning the driver was lifting off the throttle a lot. The final green circle showed a large deceleration (Turn 10) before acceleration, and my experience at Watkins Glen suggested it was too much.
The areas circled in red show a lack of trail braking. If you notice, the Speed trace falls down, and then abruptly flattens out then slightly inclines – I think of the shape at the bottom as being quite "square." That indicates little to no trail braking, which often means being unable to get the car to change direction enough to get back to full throttle early.
Let's dig into this trail braking thing a little more, from a data perspective. To the right is a zoomed-in Speed trace that shows trail braking. Notice the "hockey stick" shape of the trace inside the green circle below; the change in the rate of deceleration indicates trail braking. The lack of that hockey stick inside the red circle indicates a lack of trail braking. We all know that some corners reward trail braking, and some don't. But I wondered… if the driver trail braked a little more in some of these corners, would that result in the car rotating better, meaning he could get back to full throttle sooner?
With this in mind, it was time for me to give the driver direction for the next on-track session. From the data, I wanted the driver to focus on just two things:
More time at full throttle.
Use the brake release to help carry entry speed, get the car to rotate, and ultimately get back to full throttle sooner.
I then asked the driver to do the following in the next on-track session (ideally, I would have split this up over two sessions, but the driver only had one session left that day, so I took a chance that he’d be able to handle it all in one session):
“Spend 3% more of the lap at full throttle.” (Note, I wasn’t asking for a big change.)
“Experiment with the timing & rate of release of the brakes – focus on Turns 6, 7, 8, 9.”