This is where we get to the basics, we’re talking over- and understeer now.
Finding out what your car does, when it does and how it does it, is the start of getting the desired balance.
Your car does one of two things at the limit, either over- or understeer (neutral is a state to aim for, but no car is neutral in every corner)

What is oversteer?

Keeping it short and sweet, oversteer is when the rear of the car steps out to any degree the most extreme being a spin.
It is actually useful as it can help to steer the car.
But as many of the good things in life….too much can kill you!(or get you intimate with a hedge)

So why does the car oversteer?

When the rear tires don’t have enough grip to deal with the sideways force put through them by cornering (and/ or propelling).

they slide to the outside of the corner.

They don’t have the grip available because of a few factors.

  • Weight distribution (rear of the car is heavier / lighter)
  • Tires (type wear and pressures)
  • Braking (causing weight transfer)
  • Steering inputs (being heavy-handed can upset grip)
  • Engine and drive layout (RWD cars are naturally more prone to it)
  • Suspension & chassis setup (this is basically voodoo)
  • Cornering speed(never too much remember?)
  • Throttle (again…never too much!)
  • Weight transfer (this one is closely related to throttle and steering)

Driving the same car form the base model through to the sporty model you’ll notice oversteer increasing. (actually understeer decreasing, never slipping into pure oversteer though)

Causes of oversteer

Driving a car on the road, you will probably never see any oversteer.
Except when driving in snow (which is actually a great way to practice!) Oversteer is encountered at the limits of the cars handling so that would be on track or when the limits are lowered (snow/ice).

But what causes it?

You , you are the cause of the car oversteering because you are the one in control.

How?:

  • Entering the corner too fast:
    This causes the rear to lose grip, you’ll notice the car taking a tighter line that you were steering…..followed by that ‘OH SHIT’ moment when you realise it keeps rotating towards the inside barrier or even past and you can see the direction you came from.
    Congratulations, you have spun your car!
  • Accelerating into the corner, too early or too aggressively
    This is for the RWD cars (you know who you are!) this will overwhelm the rear tires, causing them to spin, smoke and generally scream for their lives.
    Make it to the exit of the corner and it is called a drift, otherwise it’s just another boring old spin.
  • Braking into the corner or mid corner
    Closely related to the first item, you enter a corner to fast, you start thinking maybe this wasn’t such a good idea and touch the brakes.
    Instantly the rear gets lighter, the front a bit heavier, setting up a nice rotating moment leading into the eventual spin.
    Release the brake early enough, the status quo will be restored the car continuing on it’s way safely away from any immovable objects.
  • Lifting off the throttle also known as lift off oversteer
    Lifting off the throttle does the same as using the brakes, if done in a gentle way it’s actually useful for balancing a understeering car.
    Be brutal however, and some cars will put you into a hedge (yes 205GTI at the back, I mean you!)

Other factors (than you)

  • Weight distribution
    Weight distribution and the way it is constructed has a lot of influence on the balance of the car.
    Using the hammer analogy (the head being the heaviest part of the car), if the weight is at the front of the car, the rear is light, has les grip available and will step out more easily. (think pickup truck)
    If the weight is at the back of the car, the pendulum effect will want to pull the car backwards into any immovable object it can find.(think Porsche 911)

 

  • Tires
    Running tires with less grip at the rear than the front is a good way to induce oversteer, so check for wear and always mount the same tires back and front.
    Again this can be used to alter the characteristics of the car.

 

  • Engine and drive layout
    Some drive layouts are more prone to this that others, rear drive being inherent oversteerer.
    Really not much you can do here other than lose as much weight as possible from the ‘heavy’end.

 

  • Suspension & chassis setup
    This is where (after spending some money) the fine tuning of the handling is done.
    Cars these days don’t have much adjustability built-in, so you’ll need to fork out some cash to modify parts to make them adjustable. Think changing spring dampers, geometry and such.

 

  • Weight transfer
    Softly suspended cars allow for a lot of weight to be transferred, so stiffening the springs up all round will allow for less weight transfer. (again, as with any good thing, too much will cause problems)

Rule of thumb:
The longer the wheelbase, the more time you have to react to oversteer.

How to influence oversteer?

Change driving style/driver training

Since you are the cause of the oversteer, start training, get some instruction and become a better driver.

This is one mod you’ll take to every car you drive!

Change the rear tyre pressure

increasing it will reduce peak cornering force

decreasing it will increase peak cornering force

Change rear springs or anti-roll bar

stiffer is more oversteer

less stiff is more understeer

Use different rear tyres

Only for track use really, and only if other options have been exhausted.

This would not be fine tuning!

Increase rear down-force

increase wing angles if you have wings, but even then probably only effective on very high-speed tracks.

Add rear weight (shock horror!)

Does the same as increasing rear downforce….but don’t, really don’t

Steer the car

if the car goes into mild oversteer, just countersteer and set up a nice four-wheel drift, ever so impressive!

Calm Down!

Always, you are not racing and need to get home to your loved ones.

And understeer?

You’ve  been here before, remember that time you entered a corner too fast?
The steering went light and however much you turned the wheel the car just would not turn  anymore?
And after climbing out of the hedge you saw two straight black lines in your path wondering what happened.
Meet understeer……..the enemy of all things fast

Why does the car understeer?

Understeer is your front tires not having enough grip to deal with the forces put through them by cornering (and sometimes being driven).
Why again depends on a few factors.

  • Driver input
  • Weight distribution
  • Drive layout
  • Suspension & chassis setup
  • Tyre type, wear and pressures
  • Cornering speed
  • Throttle
  • Braking
  • Steering inputs
  • Weight transfer

 

Causes of understeer

Again this is mostly your fault, though most cars being engineered with some understeer from the factory puts you at a disadvantage.

  • Accelerating to hard in a corner
  • Braking into a corner
  • Going into a corner too fast
  •          Excessive steering input
  • Not enough grip from the roadsurface due to water,  ice, oil or something else that reduces friction.

All road cars have some degree of understeer engineered in because oversteer is considered unsafe.

think of it like this:

Driving into a corner the average driver encounters an obstacle, the natural reaction (and what we are thought) is to brake (hard) and try to steer around the obstacle.
If the car is oversteery, the back-end will step out and the car could enter a spin.
If the car is understeery the front will slide to the outside of the corner and come to a stop.
No violent spinning around its axis.(and if push comes to shove, the car contacts the obstacle with the part that is best equipped to deal with it…….the front)

Other factors

  • Weight distribution
    Again using the hammer anology……if you throw a hammer, it will fly head first in the direction you threw it….it is the same with cars.
    Using non scientific language, the heaviest part of the car will ‘pull’ the most, the rest will follow….
  • Tire
    Using cheap ditchfinders on the front will never help with understeer……
  • Engine and drive layout
    The best example of a understeering drive layout would be FWD, asking the front wheel to drive and steer leaves less grip for either one or the other.
  •  Suspension & chassis setup
    all cars are setup from the factory to understeer, but there are ways around that!
  • Weight transfer
    the same as with oversteer (see my earlier comment)

Influencing understeer

How do you deal with understeer

Change driving style / driver training

Since you are the cause of the oversteer, start training, get some instruction and become a better driver.

This is one mod you’ll take to every car you drive!

Change front tire pressures

Increasing it will reduce peak cornering force

Decreasing it will increase peak cornering force

Change front suspension stiffness

Softening  the front  of the car through different springs or anti-roll bar

Use softer (or wider) front tyres

logical really, increasing grip where it is lost keeps the tire holding on longer

Increase front downforce (if aerodynamics fitted)

really only for the fast corners where downforce comes into play.

Decrease throttle

this allows the tires to regain grip.

Be as smooth as you can

being smooth won’t upset the car, making the tires work within available grip

Don’t enter corners flat-out

as my instructor said, slow in, fast out

Don’t brake in a corner

braking uses the grip being used for steering, if you decrease it, you get less steering and the dreaded understeer.

The only exception to this is if you are using trail braking…

 

This has become quite a bit longer than intended, but knowing the basics, we’re getting to the meat of the subject.