We've all heard the expressions, "I was driving 10/10ths," or "That lap was only at 9/10ths," or "This is my daily driver, so I like to drive at 7/10ths." At a gut level, we kinda know what that means. But do we?
Take a track you can lap in one minute-flat (1:00.00). if we use math to define what we're really doing, driving at 9/10ths means being 10 percent slower, or a 1:06. I don't think any driver would claim being six seconds off the pace to be driving at 9/10ths! So, what do these expressions mean, and how can we use them.
My good friend and fellow coach Peter Krause wrote an article a while back that some drivers still refer to to this day as a great guideline on the topic. I'm pretty sure you'll get at least 11/10ths worth of knowledge out of anything Peter writes or talks about!
"Tenths," and Their Appropriate Use on Track
by Peter Krause
When I describe "tenths,” or the system of assigning a relative speed, level of concentration, or demonstration of car physics on-track to someone, I usually follow these definitions:
3/10ths is driving on a flat, straight and level road with no distractions.
4/10ths is driving on a gently curving Interstate with low traffic density at a higher rate of speed than at 3/10ths.
5/10ths is driving quickly, but efficiently and at the speed limit on the street, more concentration required due to more "hazards" present.
6/10ths is a standard DE lap or an out lap early on in a race weekend, for me. The purpose may be to re-familiarize myself with the race track, enjoy a relaxed lap or just "cruise" around and, in particular, designed to take NOTHING out of the car. This is also the level of driving quickly on the Interstate with a fair bit of traffic at higher speeds.
7/10ths is a more aggressive DE level, designed to begin to "move the car around" and just a little more taxing on the car. Also, 7/10ths can be an out lap later on in a race weekend, usually the result of greater confidence and familiarity. Relatively wide variation in lap time depending on traffic and concentration.
8/10ths is an easily sustained level, requiring high levels of concentration, generally attained after the first few laps of a race or enduro when the dust settles and you slide into driving quickly and accurately, but are not locked in a battle that is external to you and your car. The car is sliding, but only at the beginning or the end of a corner and not at all corners and not on all laps. Generally laps are within .8-1.5 seconds apart and relatively consistent. This is the level I am most comfortable taking people around the track. Plenty of "headroom" and margin for error or changeable track conditions.
9/10ths is driving pretty hard, but is sustainable, repeatable, and the driver is still relatively accurate in their placement of the car. The car is now sliding much of the time, the driver is focused on catching someone or staying ahead of someone, but is maintaining control and discipline of their own mind and of the car. At this point, the driver is using most of the width of the road, but not much curbing, and is focusing on drawing large arcs with the path of the car. The rhythm is such that the lap times are generally within .2 -.8 seconds apart, barring traffic or mistakes. This is my limit for one or two "hot laps" with someone riding with me.
9.5/10ths is driving hard. More sliding, slightly quicker laps still than at 9/10ths. Less margin for error, a lot more work being done by the car. The driver is now "guiding" the car on a path selected well in advance. The car is sliding from turn-in, through the apex and is using the entire width of the paved track, plus the inside curbs. Cannot generally be sustained for more than five or six laps. I would not drive a car at this level with a passenger in it....
10/10ths is when the skill level of a substantially experienced and supremely confident driver meets the competence level of the car nearly perfectly. The car is sliding nearly the entire lap. Slip angles of 7-12 degrees (DOT radials, less on radial slicks) are sustained through the entire length of most of the corners. The entire width of the road, plus the inside and outside (if available) curbing or pavement extensions are used, every corner, every lap. The previous lap is at 9 or 9.5/10ths so that the "hot" lap is started at the greatest possible speed and with the highest possible concentration.
Typically, I drive 10/10ths for one or two qualifying laps and my first few laps of the race to build a "gap" to the rest of the competition. I also drive 10/10ths to experiment with changes made to the car or to evaluate tires in practice, not to mention putting in a "flyer" to achieve the psychological advantage of being on or near the top of the time sheet <grin>.
I may not drive 10/10ths more than a few laps during the weekend, but I pick and choose the time to do it. I feel like the car and I are balanced on a tightrope and I am constantly making tiny little corrections to adjust its trajectory, with each correction making a difference...I'm not sure this level can be sustained more than two or three laps at a time. In order to be successful at the highest level of most organized competition, you must be able to drive at this level.
11/10ths is when your talent runs out! <very big grin>
- Peter Krause
"If you believe it can happen to you, how can you possibly do the job properly? If you’re never over eight-tenths or whatever, because you’re thinking about a shunt, you’re not going as quick as you can. And if you’re not doing that, you’re not a racing driver." - Gilles Villeneuve
Driving the limit means driving the limit everywhere.
Many drivers drive the limit. In fact, most drivers do. But here's the thing: they don't do it enough. They don't drive the limit everywhere.
One major difference between elite level pro drivers and every other driver is they drive the limit everywhere, whereas many/most drivers only drive the limit in certain parts of the track.
In the illustration below, the green represents the limit, the yellow something less than the limit. As you can see, the driver on the left is not on the limit in three places. Now, this is only an example, and it's likely that where the driver is below the limit is somewhere other than where it's indicated. For example, typical places where drivers are below the limit are:
- From turn-in to the apex (despite being at the limit from the apex out).
- In the short sections between corners where the driver's mind is saying to itself, "Why bother going all the way to full throttle for a fraction of a second, when we're just going to lift out of it again?"
- Early in brake zones by not braking hard enough initially.
Now, here's the interesting thing: Even though my last example above was not braking hard enough to use up all of the tires' grip to be on the limit, some times the best thing to do is brake lighter - not at the limit - so the car is better balanced, and therefore has a higher limit for corner entry. Ahh, that elusive perfect compromise that performance driving is all about!
When you sit down with your physical track map after each session, break the track up into sections:
- Brake zone from BoB to Turn-in point.
- Trail brake zone (if there is one), from Turn-in point to EoB.
- First third of the corner, from Turn-in point until about 1/3rd of the way into the corner.
- Second third of the corner.
- Final third of the corner.
Actually make small tick marks on the edge of the track map with a pen or pencil, and then ask yourself how close the tires are to their limit in each section. Try to find a part of the track where you're not at the limit. Dig for it.
Don't get me wrong. As I've written about in the past, I understand that you may not want to drive right at the absolute limit, as you could be in your daily driver car and want to make sure you get home at the end of the day. That's okay. Then, instead of evaluating whether you're at 10/10ths in each of those sections, ask yourself if you're as close to the limit as you want to be. For example, if you want to drive at 7/10ths, then dig to see where you're at 7/10ths, and where you're not (or even over 7/10ths).
Awareness is an amazing tool. Once you become aware of something, you very often change your behavior. If you become aware of driving below the (or your self-defined) limit, your mind will typically do what it takes to get it to where you want it to be. But the key is taking the time to evaluate how close you currently are to the limit.
Oh, and it's okay to be honest with yourself!
“Box, box, box”: The phrase, used more often in Europe than in North America, used to tell a driver to come to pit lane. Often, at European (and Asian) tracks, there is a small garage attached to pit lane where the car is worked on, and therefore is referred to as the “box.”
“Pit now”: The phrase used most often in North America to tell a driver to report to pit lane (where there is unlikely to be a garage, unless at COTA, for example).
But Wait, There's More...
"Have been running the Sebring circuit for more than 10 years, and HPDE instructing with Chin Track Days over the last 3 years. After watching the Sebring track walk I knocked almost 2 seconds off my lap times yesterday. I got more out of the video than my last past professional coaching session. I highly value the content that you and Peter continue to offer that enables my students and I constant and never-ending improvement. Thanks for all you do!"
That's one of many of the cool emails that Peter Krause and I have received about the Virtual Track Walk videos; these are available to help you learn, re-learn, or fine-tune how you drive these tracks:
- Barber Motorsports Park
- Indy Road Course
- Laguna Seca
- Lime Rock
- Portland International Raceway
- Road Atlanta
- Road America
- Watkins Glen
- Virginia International Raceway
Check them out before you go to one of these tracks for the first time... or the next time.
Oh, and something else for those of you at the SCCA Runoffs at VIR! See below and join Peter at this seminar...if you want to go faster.
If you want others to enjoy what you get from Speed Secrets Weekly, go ahead and forward this one issue to them and suggest they sign up for themselves by going to SpeedSecrets.com/SpeedSecretsWeekly. But don't get in the habit of sharing these issues (notice the copyright message below) because that's just not fair. Plus, it would be a big pain in the butt to do that every week. Let them work for it like you did!
Copyright Ross Bentley, 2019
The fine print... Opinions expressed here are entirely mine and/or of the contributing author(s), and are meant to be used at your own risk... and all that other legal stuff that usually goes at the bottom that no one tends to read anyway. But it's here, right? So it's all up to you now. You're responsible, okay?