Offseason Training: Part 4 – Unbalanced Setup

Imagine you’re a racing driver and you get in the car only to find it isn’t really set up the way you like. Maybe it’s understeering too much. Maybe it’s oversteering too much. If this was a test day, you might tell the engineers that you would like the setup changed a little or a lot. But this isn’t a test day, it’s a race day, and you have to race the car you have.

Working around problems

In this exercise, your job is to figure out how to work around the problems of an unbalanced vehicle. We’ll keep the car and track the same as the last exercise to keep you in familiar territory, but we’ll change the grip at one end of the vehicle or the other. Assetto Corsa doesn’t allow you to mix tire compounds, but you can change tire pressures. The ideal starting pressure for the Miata is 28 PSI. By setting one end of the car to 40 PSI, you will reduce grip on that end enough to feel a substantial change in handling.

  • Vehicle: NA Miata
  • Track: Brands Hatch Indy
  • Weather: default
  • Setup:
    • Understeer: Front 40 PSI, Rear 28 PSI
    • Oversteer: Front 28 PSI, Rear 40 PSI

Before you begin, try to guess which setup will be faster in your hands and by how much. I think the answer will surprise you. Start with 10 laps of each setup and revisit this drill in a few days to see if you improve.

Understeer

The main danger of an understeering car is running out of room at the exit. If you apply too much throttle too soon, you will have to lift at the exit. In the best case scenario, you will lose some precious 100% throttle time. In the worst case, you will run off track and crash into something. Trail-braking helps to turn the car by giving the front tires more traction. If the vehicle has too much understeer, you won’t be able to get the rear to rotate at all. You can still load up the front so that it turns in better though.

  • Delay throttle application
  • Use trail-braking

If you find yourself running off track, you have to be more deliberate about your reference points. Make sure you set reference points for brakes on, brakes off, and throttle on. Move these around until you can lap consistently without running off course.

Oversteer

A vehicle with a lot of inherent oversteer is really dangerous. It will feel like the car is trying to kill you. To tame this beast, you must reduce trail-braking because the vehicle is already prone to rotating. You may have to separate braking and turning entirely, at least until you get used to the imbalance. You also have to be really gentle on the throttle to prevent power-on oversteer. It’s less obvious, but even a mid-corner lift can cause oversteer if it’s sudden.

  • Reduce trail-braking
  • Roll throttle gently

If you find yourself spinning constantly, your oversteer recovery skills aren’t advanced enough to drive as fast as you think you can. SLOW DOWN. Pretend this is an actual race and save the car.

Progression

In this exercise, I used the slightly faster Street (ST) compound rather than the Street 90s (SV) for no good reason.  The thresholds below aren’t in any way meant to be authoritative. Use them more as a way to gauge your progress.

  • Novice 1:06.x
  • Low-intermediate 1:05.x
  • Intermediate 1:04.x
  • High-intermediate 1:03.x
  • Advanced 1:02.x
  • Expert 1:01.x

Note that in a balanced car with 28F/28R pressures, a skilled driver can get into the 1:00.X.

Danger

Every drill exists in a context. In this drill, part of the context is “can you drive this unbalanced car safely?” As a student of driving, safety isn’t your only concern. You need to learn how a vehicle behaves in unsafe situations too. I would argue that training for disaster is even more important than training for optimal conditions. In this drill, if your oversteer recovery skills are not well practiced, you need to avoid oversteer. However, once this drill is over, you have to go practice oversteer recovery until it becomes second nature.

4 thoughts on “Offseason Training: Part 4 – Unbalanced Setup

  1. In GT7 I did a 1:04 flat with CH (hard) tires front and CM tires rear. Oversteered like crazy, and generally went faster by using a taller gear. When I switched the tires to understeer, I went 1.1 seconds faster, 1:02.9 fastest.

    The interesting thing is how differently you have to drive the cars. With an oversteer setup, you actually drive the car so that it understeers, maximizing entry speed and delaying throttle. With the understeer setup I used the rear tires much more, trying to get the most out of early acceleration. The DualShock controller isn’t great for trailbraking, and a proper wheel and pedals would make the understeer setup even faster.

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    1. It’s great that GT7 allows you to mix compounds. This is exactly the expected behavior. Since you’re using GT7 instead of AC, the times will be very different, which is fine because the point of the exercise is how to adapt to the car. Lap times don’t matter.

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  2. “I would argue that training for disaster is even more important than training for optimal conditions.”
    Exactly.
    The fastest way to get fast and safe, it to practice those car control skills (in a safe environment) that will save you when you go over the limit. This is a point often missed in most track driving programs, which seem to focus on going faster, not how to get the car back in control when you inevitably go over the limit (sometime due to no fault of your own when another car loses oil or antifreeze on track). Probably 95% of the cars I’ve seen damaged on track have been due to lack of car recovery skills.
    Practice driving a loose car in sim or skidpad is the fastest way to getting safe on track, but generally not taught by enough HPDE groups.

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    1. I think we have to adjust our idea what HPDE means. It doesn’t mean “train for disaster” or really train for anything. It means “let’s have fun driving our cars around the track in a safe manner”. Modern cars are so good at insulating you from car control skills that it’s not even possible to train most of the time.

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