Lifting at the right points...
Lifting at the right points seems early and slow, but it helps produce a faster average speed, which translates into a lower lap time.
In our test, BJ drove Dalton around the track and instructed him on where to lift, how to brake, where to get off the brakes, and when to begin to accelerate. The best entry is when the lift point is seemingly premature, and the worst entry is when the entry is delayed.
Most drivers will tell you that it feels fast to overdrive the entry. This is because it takes a lot of effort to drive the car. It is a bit exciting and dangerous, for sure, but it is not fast. Early lifting will help stabilize the car and cause it to settle sooner. Once the car is settled, it will be ready to accelerate sooner. Accelerating sooner means that our acceleration zone has lengthened. If we accelerate longer, the car will attain a higher average speed, and that is where the extra 0.1 second per straight comes from.
Backing off earlier allows us to use much less brake, and therefore, we will be faster through the normal "braking" zone. That is the area between the lifting point and the point where the car settles into its turn attitude. A lot of time can be left "on the table" in this portion of the turn.
With the entry correct and the braking phase faster, the acceleration can begin sooner and the middle phase will be faster. All three of these phases will be faster, as will the entire lap.
Over-running the mark by as...
Over-running the mark by as little as a car length can cause a slowdown of a couple of tenths in lap times. At speed, you pick your lift points based on comfort and control and never deviate.
Incorrect Turn Entry
The absolute wrong way to enter the turn is to drive in very deep, hammer the brakes, and then try to gather up the car in order to begin to accelerate off the turn. The deep entry does several bad things.
First, we have to slow the car down to the allowable midturn speed in a much shorter length of time. We can only do this by applying a lot of brake. We slow the car down quickly and probably end up slower than we could have negotiated the middle due to lack of feel as excess load is transferred to the front tires.
The "table" portion we talked about is now slower than we could have driven it, the middle is slower, and the acceleration point is pushed farther around the turn as we wait for the car to settle down. We have gained a slight amount of speed in the first phase, lost some speed in the second phase, lost speed in the middle phase, and ended up accelerating late and at a lower speed. All of this adds up to a net loss of several mph and three to five tenths per turn.
This breakdown of the turn...
This breakdown of the turn segment shows the three phases we are concerned about. The correct lift point is well before the incorrect one. This is where the fast lap starts. When going in too deep to the red line, excess braking must occur and the "table" section suffers. We could see a loss here of 3-4 mph, which carries on through the middle of the turn and down the next straightaway. The delayed entry also delays the acceleration point, shortening the acceleration zone.
What Drivers Do
Driving the car deep into the turns is uncomfortable because of the work it takes to overcome that mess, so skilled drivers will naturally back off earlier in practice so that in running 10- or 20-lap segments, they won't have to work so hard. The early entry allows earlier acceleration, and the lap times are decent.
During the year, our driver might have run in the 16.30's in practice and expected to turn 16.00's in qualifying. It would not be unreasonable on new tires to gain 0.3 second or more, but two things happened. The car was slower in the first qualifying lap and even slower in the second lap.
The first lap was driven hard to heat up the tires, and the second lap was a banzai lap intended to produce a fast time. It was executed by driving in way too deep, using lots of brake, and then, after a prolonged period of trying to get it settled down, accelerating late at a lower speed. He did all of the wrong things and it showed in the times.
At one race, I observed another driver's qualifying lap and would have sworn that it was very slow. It turned out to be the fastest time of the day. It looked uneventful, and that is exactly what it should have looked like. He backed off early and smoothly, rolled into the turns with little braking effort, squeezed the throttle early, and rolled off the turn without one wiggle or twitch. And it was fast.