Preface - (Mostly for Formula SAE Newcomers)
So you want to drive for a Formula SAE team? Or you are going to be driving and want to know what it takes to be good?
Well, first off FSAE is an “engineering competition” first and foremost. A good driver can take a car a bit further than where it should be most of the time, but it takes a winning team with a winning driver to, well… win. In 2024 the Formula Buckeyes was 100% a top 3 team without an experienced driver to push their endurance and autocross scores up. However, when 2-3 seconds is on the table in Autocross, and 20 seconds a lap in Endurance, it adds up!
For those new to FSAE, the first component to the driver decision process comes with understanding how FSAE teams function. College students pour an immense amount of time into these programs - and they have to in order to balance designing, building, testing, and fixing a car all in roughly an 8 month span (let alone learning how to do all of this stuff in the process). It’s common IMO to have people putting in 40+ hours of work per week on FSAE projects, so if you are coming in fresh, respect the commitment that these people have and understand that there are any number of more deserving people to have the privilege of driving than you. However, if you put in the time, effort, and quality of work needed to thrive, you will have a deserved chance.
That isn’t all there’s to it, of course. The best drivers for FSAE usually come from this group because they also fundamentally understand the car better than others. This is crucial when it comes to diagnosing issues, improving performance, and feeling when something just isn’t working as it's designed. There are exceptions of course. I came in and drove as a freshman - but I also had years of professional racing experience behind me. I respected the process the team wanted to take, and put in my time over the years as well. Other schools may go straight for driving experience over commitment if you have a karting/racing background, but this is typically how we approach the process.
With that preface out of the way, let’s get into what actually makes a good driver out on track, and how you can change your thinking about driving. (or rather, start thinking about driving!)
The Track
FSAE events all take place on temporary circuits outlined by a sea of cones - your standard autocross affair. My process for breaking down tracks is the same for everything across the spectrum of racing things I’ve driven. This is a general process, so some places may have small nuances that I’ll discuss at the end.
The first thing I’ll look for is figuring out my entry vs exit priority corners. All this means is determining how much time you spend in the corner entry versus the corner exit and straight. Spending more time/longer distance on the entry portion of a corner than the exit? Prioritize entry speed. Long straightaway after a corner? Prioritize exit speed. Simple. Where this becomes slightly more complex is when we start to look at how we adjust our lines and throttle application points to work within this philosophy. Let’s break down a section of the Pittsburgh Shootout track from 2023 as an example:
Corner ‘A’ has a longer straight immediately after, which indicates an exit priority. Corner ‘B’ has a very short run into the next turn, which indicates an entry priority. Corner ‘C’ has a short run into the next left kink: If the kink is flat, I would say prioritize the exit. If it’s not, then an entry priority is best.
How does this change your line? Well let’s look at Corner ‘B’ with two examples:
Think about the corner as a function of different radii. Going back to your simple high school physics, a=v^2/r, defines how we approach these different lines. We obviously want to maximize our speed, and if our lateral acceleration/maximum grip is defined by our car, the only tool we can use in the corner is the radius of the turn we are taking.
These two lines above show an entry and exit philosophy. The green line is an exaggerated exit approach. The minimum corner radius happens early, which implies your minimum speed point is also early. This opens the potential to accelerate early, and maximize speed on the back side of the corner, which then leads into the following straight. The red line shows a bit of an entry approach. The corner radius is wide to begin with and tightens up just past the apex - allowing for more speed on the approach with a later throttle application. For corner ‘B,’ an approach like the red line would be better since there isn’t enough of a run out to be beneficial.
These track maps are released ahead of time, but the maps themselves don’t always provide the same level of nuance as walking the track would show. Different levels of grip on the surface can always be a factor depending on sealant patches, rubber, or even standing water to name a few. Especially for an autocross track, seeing where cones are placed should give you the ability to experiment with lines in a few places, or get creative with where to set up outside of the standard boundaries.
This approach also applies to slaloms. Typically a slalom will have a fast entry as you want to be decreasing speed in, with a focus on backing speed up in the final section to get a strong exit. My goal for the central portion is to keep a stable and predictable balance, and is really the only time I’ll recommend driving with some sort of maintenance throttle. This helps to maximize cornering and change of direction, as the understeer from the throttle application helps to keep this predictability. FSAE cars can be quite “snappy” with their wide track width and short wheelbase, so those small tweaks to manage balance go a long way when dealing with fast steering inputs.
Understanding the Vehicle
Okay, so we have a decent idea of how to approach the track, now onto the machine itself. Your tools as a driver are quite simple. You have three -primary controls at your disposal. Steering, throttle, and brake. You also typically have a shifting system - aside from EVs and CVTs of course - but we’ll stick with the basics here. Let’s start with the simplest to work with, the steering wheel.
Steering
The steering wheel is quite basic. It won’t cause your car to transfer weight in a way that directly changes your balance, but obviously more steering input means your car turns more. Shocking, I know. You are always at the mercy of your tires, however. Tires take time to set, especially when talking about slip angle and lateral performance. Although these small formula cars will react quickly to your inputs, you still cannot turn instantly and receive an instant amount of grip. Turning too fast will not allow the tires to build their proper slip angle, causing them to “skate” across the surface of the track instead of digging into the ground. Keep this in mind when turning in for corners as well. Don’t end up making every corner an exit priority corner. Slow your hands down, start your turn in earlier than you think (typically).
Lastly, some nuances come in being able to feel the car’s balance through the wheel as you are navigating your way through a lap. Your tires will communicate a variety of forces back to the wheel, and if you’ve designed your steering system well, the peak grip of the tire should align relatively closely with the peak “force” distributed back to the wheel. Keep your hands light.
I’ve seen too many drivers in a wide variety of disciplines grasping the wheel like their life depends on it. That feeling/action is perpetuated by a fear of not knowing what the car is doing - and guess what! When you grab the wheel too hard, you dampen the forces coming through the wheel to your hands and arms. Which in turn makes it harder to decipher what the car is doing, and thus keeps the cycle going. A friend of mine from the coaching world is big on telling people to “wiggle their fingers” during the apex of a corner to keep their hands light. While this may not work for the tight and constant FSAE corners on an AutoX course, you can certainly try this on a skidpad.
Throttle
Your throttle and brake are not just tools for speeding up the car and slowing it down. Fundamentally these are how we can manipulate understeer and oversteer via weight transfer. Let's start with the throttle.
When at the limit of the tires, we are either understeering or oversteering - both of which can be achieved with different degrees of throttle application. FSAE cars are typically traction limited at low speeds (more power than grip), so it becomes very easy to get a lot of wheelspin and pass the limit of the tires quickly.
How do we use this to our advantage? This means we can flick a car into a low speed turn, and power out to effectively slide around tight turning radii like a rally car would. The problem with this - is that it's very hard to execute and relies on your driver to start with enough rotation on entry to continue "swinging" the rear around on exit. Plus, this is extra harsh on tires. If you are running a soft compound that is sensitive to temperatures, this will reduce your overall grip at the rear - which will then make it easier to get wheelspin, which will increase temps, decreasing grip, etc. It becomes a cycle we want to avoid.
Okay so what's the alternate - driving on throttle to the traction limit? Yes, but along with the difficulties of being delicate on power, we need to balance weight transfer shifting rearwards. Most of the time when you are going to touch the throttle, you are starting from a point of deceleration. Meaning, you have been loading the front tires for a period of time more than the rear, giving you more rotation. Going back to partial throttle (even 5%! every bit matters here) will shift weight rearwards and hurt your ability to turn. If you are getting back to throttle before you are done with your maximum cornering point, it will make it harder to get back to full power and maximize your exit speed.
The TLDR here of applying throttle correctly is waiting until you're ready to unwind the wheel in your corner. This isn't always directly possible depending on the type of corner, but by utilizing the general principle of patience with when you get to power, you open up the door to achieve better exits and better entries.
Braking:
There's a reason why I led with describing the throttle before braking, and that's because your exit should define your entry. If you get to power too soon, you mask the true potential of entry speed that you can carry into the corner. Braking is super important, because we need to match our entry to those goals that we defined by our track positioning and throttle approach. Unlike your throttle application though, once you commit too deep to your entry - there's no going back or making an easy correction.
Many of the things I'll be mentioning here will be my own take/FSAE specific variation of the absolute gem of an article put together by Dion and the Blayze team here (featuring my own data-cameo). I highly recommend you take a look if you're interested in reading about this section a bit more in-depth: https://blayze.io/blog/car-racing/braking-masterclass-for-racecar-drivers
The first couple of things I want to discuss deal with some common misconceptions that I run into frequently; the 'ideal' brake trace and trail braking. Using the data screenshot from the Braking Masterclass article (my LMP3 data from Mid Ohio a few years back), you'll see a variety of different approaches depending on the corner.
One trend across the board is with the 'triangle' shape to each of the traces. This is commonly referred to as the 'downforce' brake trace, as it maintains a threshold of braking as your speed reduces. As you slow down, your levels of downforce get reduced, meaning you have to reduce your brake pressure actively to cope with the change. In some corners, you'll see a very short brake trace, and in others you'll notice a lot of trail braking - with a little bit of brake pressure being applied deep into the corner. This is most noticeable in the Keyhole and the Carousel:
Why is that? Well, these corners are particularly long in duration, and I have an exit goal in mind. I want to get to power late here. So, I'll extend my brake zone deep, which means pushing it into the corner itself. Due to the understeer nature of the car on this particular weekend, I'm also trying to shift weight forwards and increase front grip. Other corners where pure rolling speed is more important, or that are fairly short in duration, have a shorter period of braking with a faster release.
Our entry goals fundamentally come back to understanding the track. Let's dive into the FSAE level again, using some data from the Pittsburgh Shootout in 2023. For a corner like this, we have a long-double apex that I want to "diamond" - drive in hard, get a lot of rotation done, and back to power in a relatively straight line for the exit. Much like the LMP3 at Mid Ohio, I'm approaching the brake zone with this goal in mind.
Other corners, like below, may benefit from more rolling speed. For these corners, it's important to roll in lighter on the brakes. The longer release helps to maintain good rotation to the apex, while looking to get a strong exit at the same time.
But how do we know what type of brake zone to apply? If you want the long answer with plenty of examples, check out the masterclass article - otherwise this question segues great into the final major category here:
Balance:
Balance is key, and depending on the type of corner, we want a certain type of balance. Now, a neutral-steering car is desired most of the time but this isn't exactly achievable all the time. My ideal car, especially for FSAE, is one that oversteers a little at low speed, and understeers at high speed. Think of rally cars in tight corners or hairpins where they pull the handbrake to rotate the car quickly. At higher speeds, your ability to make corrections to the steering wheel to prevent oversteer is significantly hampered by the time to react. At low speeds, you have much longer to correct any handling imbalances than at high speed, which is where the controllability of an understeering car comes into play.
Chances are, your FSAE machine will not handle perfectly! This means you need to adjust your throttle and brake applications to work around what your car is doing. Too much oversteer? Back up your corner entries and brake earlier and lighter. Too much understeer? Brake harder and deeper to try to get more weight transfer forward and increase your rotation. We need to start from the right set of fundamentals to find the maximum pace and adjust from there. Chances are, if you have the right idea about your ideal throttle and brake applications by corner - but can't achieve those for whatever handling reason - you will have a better idea of what direction the car needs to go in order to be faster.
All of these idealizations in balance stem from what a good driver can take advantage of. Keeping a car at its 100% maximum is a very difficult task, and good drivers are constantly on this tightrope of the grip limit. Lots of minute corrections are made as the car is thrown in and out of the limit constantly. An oversteer-y car will always be much more difficult to keep at this limit. For that reason alone, I will always try to engineer a car with a little bit of understeer everywhere for inexperienced or learning drivers.
Closing Thoughts:
Dynamic driving at the limit is not an easy thing to get right, but with the fundamentals in place, my workflow usually starts with this process:
- Identify goals by corner: Entry or exit priority & ideal throttle application location
- Work on exits first to shape the corner: "How much throttle can I get away with? Do I need more or less rotation to achieve my exit goals?"
- Match entry speed to the corner: Brake application type, brake release, etc.
From there, it's a matter of gradually increasing entry speed until you find the limit of the car. That's it! Getting the feeling of being able to maintain a car at its limit comes with time, and the same goes for reaching the limit and getting up to speed quickly. If you start with the right process, it will make finding those last couple of seconds a much easier and actionable process.
The ideal driver for FSAE competitions (IMO) is one that is reliable. I've seen plenty of teams throw away easy victories in endurance due to a plethora of off-tracks and cone penalties. There's a lot of pressure on your drivers to execute on track - this is the culmination of an insane amount of hours invested from each team member. If you have enough practice in these dynamic environments, with a set approach, it helps to build confidence when going out and executing the real thing. Testing time is important not just for car development, but getting your drivers comfortable to execute when it's time to put the pieces together.
That's all for now. There's a lot more I could go in depth with on individual points, but I wanted to get a foundation and starting principles that the 'pros' use out on track. If anyone has any questions or wants some additional clarifications, don't hesitate to reach out!
- Colin