Most drivers realize that great precision is needed to go fast, “inch or millimeter precision” referencing the racing line, brake application point and getting back to power and full throttle as soon as possible. These are all real and worthy goals but there is so much more and honestly that’s when driving starts to get interesting.
Beyond the above statements there are more layers when it comes to what great drivers are doing. You hear minimum speed (or rolling speed) often these days (focus and phrasing seem to go in and out of fashion much like anything else). “Gotta’ get those minimum speeds up” or “carry more rolling speed into the corner”, sounds great but how the heck do you do that? Most often answer I hear is release the brake sooner, it superficially sounds about right, it will allow you to add minimum speed. If I enter at the same speed at turn in but trail off the brake sooner it will indeed raise my minimum speed but that shouldn’t actually work, the only way it would work is if you are over slowing the corner and happen to have underutilized tires (you aren’t actually at the limit) then by all means carry in a bit more speed but…what if you car is actually at the tires limit at least on one end of the car? I would optimistically assume (from the safety of behind my laptop screen) that you nearly all better damn well be at the limit of adhesion of at least the front or rear tires while you are cornering on a race track (or what’s the point?)
How do you feel about raising minimum speed now? The people who are recommending that’s what you do (in all likelihood doing a data overlay) giving you “some low hanging fruit” “If you just carry a bit more speed it’s worth half a second in that corner alone”. You are already at the limit but I’m losing a half a second? That makes no sense. You would automatically then think of the car as being the issue, it must be lacking grip (and if the overlay was the same car then the tires must be gone vs. when the reference lap was recorded) because you were at the limit, you felt the car slide.
Now people do sometimes imagine they felt the car slide. That comes from a perception reality disconnect. It’s surprisingly easy to do and comes from the correct desire to anticipate a slide rather than react to it. To exactly match the adjustment (correction) with the loss of grip. Sometimes people get a little too proactive and fix things that never happened but truly believe they fixed something (a bit of a paranoid “better safe than sorry mentality”). This can technically occur well below the limit but you would like to think they are at least close.
The other possibility is the slow driver that is lacking in confidence, the driver driving at their limit (not the cars), the limit of their comfort. This is also a perception reality disconnect. They have an inflated perceived risk that is slowing them down. What fixes all of this? Car control training; spending copious time in the paddock on a skid pad, slalom, braking, corner and putting them all together (simple) autocross building feel and confidence in a safe but relevant environment (please read Optimum Drive for a lot more on all of this, these blog posts build on the book’s foundation).
To finally answer the question of how to raise minimum speeds when your car is actually already at its “limit” in the corner (not perceived, an actual slide is imminent). The first thing to understand it the limit is never understeer or oversteer. Those are unbalanced limits which are below the minimum speed the car in its current form could corner at. The reason it that while two tires (front axle or rear) are indeed at and/or over their max the other end of the car isn’t, that means the overall car grip is not optimized. So, while the car is certainly cornering hard it is not at its actual limit until all four tires are at the limit. Understeer and oversteer are not limits they are simply indicators of an imbalanced car cornering too hard. This is where the minimum speed can be raised by changing the balance and therefore being able to increase entry speed. So, to the original point it is not just “rolling off the brake sooner” too raise mid corner speeds it would actually properly require a slightly later brake application with the intention of carrying more speed into the corner itself while balancing the car better with the brake release (timing with steering input)
Remember to focus on the timing of your inputs as the primary tool for car balance, not car set up. Only when you have exhausted every possible variation of trail braking vs. steering inputs should you ever consider touching the car. Everything you change on the car to fix balance has an effect on the car in every other corner (some negative some positive) and it becomes infinitely complex almost instantly on the gain and loss equation for the full lap/session/race while if you change what you are doing in that one corner to improve balance it only effects that one corner and only positively (or you wouldn’t do it). Think of the modern F1driver and steering wheel where they are adjusting everything dynamically always to help minimize the compromises the diff and the brake bias, anti-roll bars etc. (plus they are adjusting everything they can driving the car to minimize the adjustments required). It all gets a little crazy, keep it simple, leave the car alone with just a hint of mild understeer as your car setup balance base and work from there (any decent driver can work from that balance to optimize the car balance in any type of corner). How?
Timelines, think about timelines when it comes to optimizing car balance. Our car setup has mild understeer but the only time (we will allow) the car to understeer is in a very long carrousel type corner where our balance tools lose their reach (you can only trail brake so far realistically). The two timelines and your steering (steer in steer out) and your feet (Initial brake to brake release, throttle to full throttle). It is a subtle shifting of these two timelines that adjusts balance. There is of course infinite variability within the individual timelines but is the interaction between the two timelines that adjusts balance. Specifically, the timing of the brake release with the steering input into the corner and there is one more variable in play that guides us. Our mild understeer car is not always a mild understeer car. That is an average of what the car does relative to corner speed. Independent of our input just talking about car physics the lower the speed the greater the understeer and the faster the corner the less understeer (which is why a rear wing/spoiler is nice to help offset the growing oversteer tendency). With that we can see the timeline shift at its most basic form. The slower the corner the more we shift the braking timeline into the corner…the more we “trail brake”. Conversely the faster the corner the more we shift the braking timeline earlier…the less we trail brake. Now there is no excuse for understeer or oversteer, it is set by the driver and the whole responsibility of how the driver juggles the timelines to balance the car in any given scenario.
The other variable; line. In any basic school you will be shown the advantages of the late apex. It is a great place to start. It is important to start conservatively but the why behind it is important to see why it is variably later not just later. The premise is that we gain enough of an acceleration advantage with the late apex that it more than offsets the time loss of the tighter entry (more on this later). This is due to acceleration being tied to steering angle (the straighter the wheel the more throttle that car be applied, understanding that a car cornering at its limit is very sensitive to braking or throttle). We gain more than we lose and that’s why we do it. You could immediately see that would be car power dependent, if the car is low power you do it less or maybe not at all and if the car is high powered (all relative to grip) you would do it more. If the corner leads onto a straight the length of the straight also effects the benefits (longer straight, later apex). So like balance timelines vary with speed so do apexs with the added complexity of car power and does the corner lead onto the straight. The late apex is only for slow corners since that is where traction issues of acceleration exist (this has to do with tractive force diminishing with speed) and therefore the benefits of the late apex occur. By about 100kph (62mph) the apexes mostly go back to the fastest geometric center that gives you the maximum constant radius.
One last trick: So, in those slow late apex corners if we shift the apex later to get to it we turn later (we get a tiny benefit from being able brake later since turn in is moved down) but that late apex cost a few tenths with slower speeds the tighter first third of the corner requires. Everything is a compromise and as discussed we do it because we gain back on the exit more than we lose on the entry. What about the possibility of minimizing the compromise? Minimizing compromises are really where the great earn their keep. Physics are physics so you might think the compromised line is the same for everyone but …that is absolutely not the case. This is where we can take balance to a whole other level. You may have heard the word “rotation” it is an intentional (trail brake induced) mild oversteer only in that extra tight first third of a late apex corner. It is done for the same reason everything is done, it is simply faster when done correctly. Rotation is part of a main topic of Optimum Drive called “Zero Steer” where you are using rear slip to steer (the wheel) less. It is very advanced and makes the car turn more efficiently everywhere gaining the final tenths of cornering speed. It requires very fine motor, granular timeline shifting. Back to the rotation, if you can turn the car faster due to the rotation (while maintaining minimum speed) you have a real advantage because you can shift your turn in earlier and still make the late apex which as you might guess reduces the amount of time (and distance) to get to that late apex. The net net is the 0.4’s you might loose on the entrance to gain 0.5’s on the exit goes down to a 0.2’s loss on the entry with the same gain on the exit.
This is why it always come back to feel and car control, you can only get so far without it. Once you approach your perceived limit it is only your feel that can adjust balance to raise those minimum speeds and how fundamental understanding of your balance responsibilities determine the actual balance and steering efficiencies of your car. So, the next time you ponder an innocent statement or observation like “raise your minimum speeds” you realize the complex skillset that actually would allow that to happen. It isn’t surprising that going faster is so hard after a point. If we have ourselves convinced that speed only comes from car placement precision and great car setup we are completely missing what make great drivers great…it’s all about the feel.