Q&A with Ross Bentley
Q: “I have been pondering EoB (End-of-Braking) after attending your Improve Your Braking & Corner Entry webinar. You said we should focus on the EoB, rather than BoB (Begin-of-Braking), just like we are driving on the street and trying to stop before the traffic light. I’m still not sure if I understand that completely. On the street, when we brake for the traffic light, we probably use 20% to 50% of the braking power of the car. There is a lot of room for us to modulate the braking, harder or lighter, during the entire process to get us to stop perfectly at the white line. On track, we are probably using 95% to 100% of the braking power right from BoB. There is not much room to adjust the braking distance if we brake too late so we can still come down to the optimal speed at EoB. The question still in my mind is how we can focus on EoB and still consistently hit the brake at the right BoB point that leads to the optimal speed at EoB. Could you share some more insight? Thanks a lot! The webinars were all very inspiring. Please keep them going!”read more
Q: “I’ve been autocrossing for about 20 years. I’m not a national champion, but I generally run slightly behind the national champs that run with our club and I usually finish in the top 10%. Last season I took on a co-driver of national caliber and ran data (SoloStorm) the whole season. Initially what I learned from the data was that we did many things in a similar fashion, but he made much more use of the throttle than I did. Trying to force myself into using more throttle closed the gap with him a little, but also resulted in a lot of spins. After looking at things more closely, I realized that he was putting the car in better positions to be able to use the throttle more, but the distinction is subtle enough that I cannot usually tell much of a difference in our line from the data. So, my question is… what is the best way I can learn more about car position and how to know if I am positioning the car in the most efficient way?”read more
Q: “I have a question as someone who is a sim racer, and not a real racing driver, but I still want to ask how I can practice to become a faster driver? I’ve read your book and it has been very useful, but I’m still not where the fastest drivers are since I’m around 2-3 seconds off the fastest times. I feel like I’m doing everything they are in terms of braking, lines, etc., but still can’t get to their times. Is this all due to me just needing to practice more or is it over for me in terms of getting faster? If it’s due to needed practice then how exactly does one practice getting faster? I’m willing to put in all the time and effort that I can since my goal is to be as fast if not faster than the top guys (also some racing drivers have said one of the ways into racing is e-Sports because some events offer a race season as a prize). I just need to know how to get faster.”read more
Q: In racing & performance driving, when is it not worth it to use more track if it means driving a longer distance?
Q: “We are taught to use 100% of the available track, to increase radius to increase mid-corner speed for a given lateral G capacity of our tires. At what point are there diminishing returns for using the entire available track versus the shortest distance? I have always wondered this. Turn 7 at Portland International Raceway is a good example, as they widened the track a few years ago and I see some drivers use it all, and some not. You can keep imagining if we open up the track more and more, eventually there must be a point where it is no longer beneficial to use all the track available, right?”read more
Q: Tell me about the priorities when performance driving – the line, exit speed, braking & mid-corner?
Q: “I am an instructor with PCA and often suggest that students review your work. One particular article, that I can’t find, described your analysis of thousands of hours of data and your conclusion that lap speed was affected by 1) line, 2) exit throttle, 3) braking, and 4) mid-corner speed, which is probably taken care of it if you get the first 3. I thought that it was very useful for novices that seem to want to work on everything at the same time. Is there a link somewhere to this article?”read more
Q: “I have a question about memory. I’m one of those drivers that can’t really remember what I did in the last corner, let alone what I did one or two sessions ago. What can I do to be able to retain that information so when I look at the data, I can assign my actions to the outcome of that sector or lap?”read more
Q: What is the best way to deal with cold temperatures on track? I recently drove in the second group at a Super Tour event at Road Atlanta, with temps around 40 degrees. It took me several laps to get the tires up to temp, and in the first few laps I had to make two big corrections. The top drivers, though, were able to drive within a couple tenths of their best time from the day before (when it was warmer), by the second lap.read more
Q: “What is your opinion on hearing levels and controlling them? In my Radical, I usually don’t wear ear plugs. Even though I don’t think I am picking up on all the sounds available, I do notice that if I do use ear plugs, I think I’m missing something. But I do feel calmer while driving. I did say “feel,” as I don’t have anything to back that up. What is your opinion?”read more
Q: “I’m off to a local track for an open lapping day soon in a new GT Mustang. Being my first time, what should I focus on above everything else? I know some just want to go as fast as they can, but I’m more into learning a little each time I go to the track so that over time my speed and technique come naturally.”read more
Q: “I seem to do well in practice and qualifying but when it comes down to competition, I choke. The only time when I actually did well was when I was extremely dehydrated and on the point of passing out. All I wanted to do was finish the runs and get out the car. I’m guessing I was in the mindset of fight or flight and not really caring about the results. But in turn I podiumed with the best drivers/cars in my series. Do you have any tips, podcast, books or just some insight you can recommend on driver mentality? I seem to get too into my head and it’s tough to get out.”read more
Q: When racing in the rain, how do I know when to start slowing down for the first corner if I can’t see?
Q: “I’m struggling with how to find reference points and maintain good vision (and stay calm!) when starting a race in the rain. I’m usually pretty far back in the pack, and the spray/mist thrown up from the other cars sometimes completely obscures my vision (regardless of windshield wipers, Rain-X, etc.). Here’s my in-car start from a recent PIR race: https://www.youtube.com/watch?v=WWwsea8PXts. In this case, I backed off way early because I just plain couldn’t tell where I was or when the chicane was coming up. Plus, I didn’t want to come in too fast if there was a pileup. Do you have any advice for how to handle this kind of situation?”read more
Q: “Specifically, on the entry phase, how does one determine whether it is steering (amount of steering or rate of input) or braking input (or more generally the rate of deceleration in a linear sense) that is the cause of over/understeer while turning in? More briefly, how does one know if they have applied too much linear deceleration or tried to induce too much rotation?”read more
Q: I am new instructor and will be instructing a student with only the left seat – I can’t be in the car with the driver. What are things that you watch for with your student while you observe him from outside the car and standing at a corner?read more
Q: I am a track day guy and get out on track about 6 times a year various road course tracks. This year I switched from a modified street car to a full-on race car for track use. The race car I am driving understeers and rotates very easily. This is very different from the previous car which had a more neutral setup. Rather than start the process of adjusting the car’s setup to match what I had previously, I am trying to adjust my driving style to match the car’s setup. In order to get more comfortable driving a car with understeer, I was wondering if karting in between track events would be a good way to transition my driving style to match the car’s setup? Do you have other suggestions as to what I can practice to get more comfortable with this new setup? Thanks in advance.read more
Q: I recently crashed my track car coming out of turn 12 at Mid-Ohio. While I have been doing HPDEs for 10 years now, this was my first time at Mid-Ohio, and my 5th different track that I have been to. I am writing this not for sympathy, but to share with your readers some mistakes I made, and also to learn from it. I’m hoping you can help with that last one.
This is my second season in a modified 2007 Cayman S, after driving 911s for the previous eight years – they handle different. I requested and was given an instructor – he was a good one and an especially good communicator. I asked if I could go out with him in his car (a 993 911) and “see” his line. We did and then his communicated line made more sense to me. I then asked him if he thought the Cayman should follow that line too? He had never driven a Cayman so I asked him if he’d like to and he did. He dialed it back a bit but drove it 5 laps using the same line. Then we swapped seats and on the very first lap I lost control on the exit/track out of turn 12 (Thunder Valley).
His line was a very early apex (riding on the right-side curbing, almost off the track) whereas I had been doing a mid to late apex. The turn finishes with a crest and downhill and you track out to the left curbing, but stay off of it, as it was known to be slippery. As I tracked out and made a very slight right turn my car oversteered or maybe “power oversteered” which a Cayman can do easier than a 911, and the disaster began. The car made four fishtail oscillations and the 4th ended with the right front hitting the wall on the right just past the tire wall on the right. We came to a stop 180 degrees from the contact angle directly under the pedestrian bridge. We were okay, minus some minor lower back soreness and mild headaches. The car, not so much.
So what can I learn from this. Well first, I admit that I had not studied the track or even watched any track videos. I was busy with family commitments for the two weeks before, and a 3-day DE the weekend before Mid-Ohio. Two, I should have tried my instructor’s line with it dialed down a bit, though I do remember saying to my instructor, “I’m not going to go try and emulate you right off”. And three, what was I thinking with less grip in the back than I was used too?read more
Q: I drive a 2017 Mazda MX-5 for fun on track, no competition, just always trying to learn and improve. When driving into one or more corners and the car understeers, how do I know when it is me entering too fast versus when the car setup can be improved? I don’t have access to a skidpad. I know I could go slower into the corner or adjust the line a bit, and 9 times out of 10 it’s probably me that is the problem. But how do you know when understeer is a setup issue?read more
Q: I’ve been looking at the telemetry data and onboard footage of faster drivers to improve my driving. I’m at the point where I understand what I’m doing wrong and what I can do better conceptually, but I can’t seem to apply it when I go out on track. What’s confusing me is I don’t understand what exactly I’m doing wrong when I’m in the car. For example, if I need to use less brake going into a corner, I’ll tell myself that before the corner, but I just end up repeating the same mistake as before. How do I figure out what exactly I must do with the controls by looking at data?read more
Q: Until this year, I have been driving a Cayman street car that was modified (suspension, roll bar, etc.) for track use. This setup was a compromise between track performance and drivability on the streets. Over the winter, I purchased a used Cayman race car that ran in the IMSA ST class. A friend who is an SCCA racer, looked at one of my track videos from VIR and explained that the car is set up for people graduating from karting to racing. In his opinion, the car rotates very easily in the corners and he recommended avoiding trail braking in the car. When I was at Watkins Glen last month, I noticed that if I released the brakes too quickly, the back end would tend to come around fairly quickly. In retrospect, I believe this is what you and Peter discuss in your track walks that I was never able to replicate in my previous car, so it caught me off guard, but I was able maintain my composure and control of the vehicle. What’s the best way to adapt my driving to the way my car handles?read more
Q: I am relatively new to your podcasts and advice columns and have already benefited greatly from the fantastic information you share. I have been doing HPDE type track driving for a handful of years and just got my SCCA competition license this year. I have the opportunity to join a Champcar team for a 24-hour Enduro and anticipate some nighttime duties. I have only one weekend of experience at VIR from six years ago. What are your thoughts on the added challenge of nighttime visibility especially with my limited track knowledge? What do you suggest as the best way to prepare and what other difficulties might I expect to encounter?read more
Q: I’m really having trouble understanding what slip angle is and how it works. Is it something you should feel? Is it like or does it feel like oversteer? How do I know what slip angle I’m at? What differences does it cause to my lap time? And most importantly how to do it?read more