Published: February 17, 2013; updated: August 13, 2013
Today we are going to look at some situations that are not obviously wrong, but ones where opportunities for improvement are possible.
At novice level, the instructor would not even mention many of these situations that do not involve the car potentially going off track. At intermediate level, the instructor is likely to give corrective actions to the driver without going into much detail as to what the driver is doing and what the corrective action is meant to achieve. As an advanced driver, you are expected to recognize these situations by yourself as you are driving on the track, formulate a plan of action to deal with them the next lap, and fix them.
Holding Constant Steering Angle Through The Entire Turn
While this does work, better lap times can typically be achieved by having a lower apex speed and higher exit speed.
The important part here is the car requires a substantial steering angle at track out to stay on pavement, i.e., if you unwind steering at all the car will depart the pavement.
While you are holding the steering angle, you are unable to accelerate, because you are using all of the available tire grip for lateral acceleration.
A driver who can unwind steering at track out will have higher exit speed and therefore lower lap time.
How can you gain the ability to unwind steering at track out? You must get more of the rotation done earlier in the turn, such that there is less rotation required at turn exit, which will allow you to use freed up grip for forward acceleration.
Which means, you need to enter slower or bleed off more speed before turn in and apex, in either case achieving a lower apex speed.
- Observation: constant steering angle through the entire turn
- Issue: exit speed too low
- Cause: entry or apex speed too high
- Solution: reduce entry or apex speed, accelerate from apex to achieve a higher exit speed
Accelerating From Turn In
This is when you are on power, possibly even flat out, as soon as you turn into the corner.
Apex is supposed to be the slowest part of the corner, because it is the sharpest one. If you are accelerating from turn in, your turn in speed is too low. Assuming you take the corner at the limit of tire grip, you are using the tires completely for lateral acceleration at the apex; if you are able to have a higher apex speed than entry speed while using the tires entirely for lateral acceleration at the apex and, consequently, only partially for lateral acceleration at turn in - your turn in speed is too low and you are wasting traction at turn in.
The solution is, quite simply, to enter the turn with more speed.
This requires a certain amount of confidence, especially for higher speed turns, higher horsepower cars, or turns with little or no runoff.
There are some unusual corners, such as turn 7 at Watkins Glen, where acceleration from turn in is possible and normal. In most corners it is an indicator of entering too slowly.
VIR turn 10 is a perfect example of a corner where many drivers are flat out from turn in due to entering too slowly.
- Observation: flat out from turn in
- Issue: losing time at corner entry
- Cause: entry speed too low
- Solution: enter at a higher speed
Not Using Full Track Width At Exit With Braking At Corner Entry
You braked for a corner, hit the apex but did not need the entire track width at the exit. What does this suggest?
If you answered "you braked too much", you are correct. Not needing full track width at the exit suggests apex speed was too low, and in turn entry speed was too low, and given that you braked for the corner, the conclusion is that you braked too much.
Brake less and enter the corner at a higher speed.
- Observation: not needing full track width at corner exit after braking
- Issue: losing time through the entire corner
- Cause: entry speed too low
- Solution: brake less, enter at a higher speed
Not Using Full Track Width At Exit Without Braking At Corner Entry
This is perfectly fine. If you drive a corner flat out, you do not need to track out any further than the car wants you to. Excessive track out simply costs you time.
Note that it is frequently possible to hold the car on a tighter line but the sharper steering scrubs off speed through the corner. This is a very fine point and typically one that needs data to properly evaluate.
Lifting (Off Power) Past Apex
This causes corner exit speed to drop, often more than the driver realizes. Because exit speed is of paramount importance in most corners, this is a serious issue.
Most drivers lift because they fear they will not fit into the track at the exit. As a recovery mechanism, lifts are fine. The issue is if a driver keeps lifting in a corner preceding a straight every lap, without realizing what they are doing or what it costs them.
The cause of lifting past apex is almost universally the apex being too early. There are some exceptions, primarily for track surface conditions. The usual scenario of an early apex tends to happen more to drivers of high horsepower cars that can enter corners with substantial speed. Without discipline it is easy to enter a corner just a bit too fast or turn in too early, resulting in a lift past the apex.
The solution is to execute a later apex, possibly reducing apex speed to make the later apex possible. Any loss of speed at the apex will be more than made up by increased exit speed, if the driver is able to stay on throttle from the apex forward.
A slight modification of this scenario is when the driver gets on power hard and subsequently lifts, whereas it would have been possible to get on power more gently without lifting. At first sight, this might appear to be a throttle application issue - throttle was applied too hard. However, the real issue is the apex chosen was too early for flat out acceleration. Cars will typically benefit from running a later apex and accelerating flat out compared to feathering throttle through a turn. Besides exit speed, the time spent driving fast on the straight prior to the corner makes a difference - a later apex allows the car to spent more time on the preceding straight at high pseed.
- Observation: lifting past apex
- Issue: exit speed is compromised
- Cause: early apex
- Solution: later apex, with lower apex speed if necessary
Running Out Of Pavement On The Inside
At novice level this is caused by turning in too early, and at intermediate level early turn in is still a real possibility.
However, another possibility is turn in speed being too low. This happens especially with intermediate drivers attempting to take a turn faster who change their corner entry too much at a time. A good example is Summit Point turn 3 - it calls for a slightly earlier apex than might first appear, but dropping turn in speed requires a later apex to fit into the turn. A driver who moves their apex up and unintentionally enters the turn slower can find themselves running out of inside track room. The solution here is not to enter later but to increase entry speed.
- Observation: running out of track on the inside
- Issue: steering correction/lift at track out
- Cause: early turn in or insufficient entry speed
- Solution: later apex or faster entry speed
Running Out Of Pavement On The Outside
Depending on whether the entire track was used leading up to the situation, this could be caused by an incorrect line (if the car missed the apex) or excessive speed through the corner (if the car hit the apex).
If the car missed the apex, it is important to adjust line rather than speed, because line depends on speed. Otherwise next lap you could find yourself running out of pavement on the inside.
If you hit the apex but do not fit in the track at track out, the turn likely does not open enough for your acceleration. The solution is typically a lower apex speed and a later apex.
- Observation: running out of track on the outside
- Issue: giving up exit speed
- Cause: missing apex or corner speed too high
- Solution: tighten the line and hit the apex or run a later apex
On And Off Throttle Throughout The Turn
This is when the driver makes multiple throttle corrections in a turn.
The cause is usually not looking far enough downtrack. Specifically, not even as far as the corner exit. As a result, the driver is "surprised" by the corner, possibly even more than once in the same corner.
Solution is to look at corner elements - turn in, apex, track out - earlier and mentally disciplining oneself to start looking at the next element earlier.
Generally speaking, good drivers will look at the braking zone while in the middle of the preceding straight, at the turn in point before they get to the braking zone, at the apex when they are in the middle of the braking zone, and at track out as soon as they turn in.
- Observation: on and off throttle through the turn
- Issue: giving up exit speed and time through corner exit
- Cause: not looking far enough downtrack
- Solution: look further downtrack
Corner Entry Understeer
This happens to just about everyone, given that most cars are set up to understeer to varying degrees. However, there are recipes for this issue beyond entering corners slowly.
The cause of understeer is insufficient front end grip for the speed of the car and attempted rotation. At novice level, the solution is to reduce the speed of the car until the front end grips. While it does work, entering corners slower gives up lap time. Intermediate and advanced drivers can do better.
A middle-of-the-road solution is to trailbrake into the corner. Trailbraking keeps weight on the front tires at turn in, increasing the available grip. Thus the car is able to perform greater rotation with the same speed.
Cars which exhibit strong understeer at corner entry may need trailbraking to perform the initial rotation even if they can take the apex faster. In particular, this applies to cars with welded differentials.
A more difficult solution, and one that tends to require an almost-balanced car, is to use trailing throttle oversteer. This means staying on throttle right until the turn in point and lifting just prior to turn in. When done right, this can transform a corner where the driver brakes lightly into a corner where the driver only lifts, with corresponding gains in lap time.
- Observation: corner entry understeer
- Issue: missing apex or taking the corner too slowly
- Cause: insufficient front end grip
- Solution: trailbraking or using trailing throttle oversteer