Team Oneil Rally makes great instructional videos that are designed to make you a better driver in both racing and daily situations. This quick classroom session is one of the best. If you are even remotely familiar with racing, you have heard of the "Apex" of a corner. The apex is the point where the car is closest to the inside of the corner and can also be described as the point where the car is traveling the slowest through the corner. There are three different methods discussed in the video: Early, traditional and late apexes.
Early Apex: (Red Car)
The early apex is when the car reaches the inside of the corner too early, leading to a shallow approach that requires slowing down mid-corner to stay on the road. Having to suddenly brake in the middle of a corner is a great way to lose control and ruin a lap time or worse in normal driving, end up in the guard rail.
Traditional Apex: (Black Car)
This is the go to for most racing situations. Hitting the inside of this simple corner right at the halfway point allows the car's arc to be much wider than that of the road. A wider arc equals more speed. The problem with this line in real world driving is that it assumes you know the corner exit perfectly and there is no room for error. With zero room for error on a road that you don't know well or changing conditions, the traditional apex can spit you off the road at the end of the corner at even the smallest mistake.
Late Apex: (Green Car)
The preferred method for rally racing and also very useful on the street. The entry is the same as the traditional apex, but you hold outside a little bit longer and slow down a little bit more. You then can turn in and hit a later apex which leaves you closer to the inside of the corner on the exit, allowing for a large margin for error.
If the car gets a little tail happy under throttle, hitting a late apex means you are straighter on the exit. It also helps in the real world on a road you don't know well. If a corner increases its radius at the end and you didn't know about it, that late apex technique could save you a trip to the body shop.
Another great advantage to hitting the apex late, is to set up the next corner. If you get through corner one of a series as fast as possible but are set up wrong for turn number two, you lose any advantage you had very quickly.