Is the Carousel a single, double, early, or late apex? There are two sets of turtles for sure. Though if you look at a map, the first set of turtles is at the geometric apex.

In my version, I brake on the left and turn in at a point that feels a bit early. I trail brake down to the first apex turtle and then while the car is going slow, I rotate it a bit more holding a tight line.

As I approach the 2nd apex, I open the wheel a bit and get on the gas as much as I can. I unwind in a fairly straight arc out of the corner. When I track out, I then kink the car straight again.

Opinions?

Peter, any idea where you start braking into T8? 100, 150, 200 mark?

Hi Peter

With my cars (2002 and e30 M3), I favor a late braking on the left, trail brake until hitting the patch of grass right before the concrete turtle on the right (inside) (which makes it a very early apex). and as soon as hit that patch, I very gradually squeeze the gaz while opening the steering wheel. Basically, I do a very early apex, and increase the distance between the car and the inside edge of the track right after. That works with a well balanced car. My goal is to squeeze the throttle ASAP. Many cars prefer the double apex line.

But if it's wet, I take the rimshot to decrease stress on tires...

The theory says the line through a 180 degree symmetrical turn varies with its radius.

Short radius 180 deg. are called hairpin and should be taken " slow in-fast out " using deeper braking and a late apex.
Large radius 180 deg. turns are called carousel and should be taken as a double apex.

A carousel should be enter fast and trail braked till the first apex, the slowest part of the turn being between the two apexes.
At mid turn you should be on the throttle and convert the last half of the turn in a straight line going over the second apex.
So I totally agree with you Peter, as your description follows the theory.

The main variation in this line is dependant on the lenght of the straight comin in the carousel compared to the lenght of the straight going out of the carousel. If the longer straight precedes the turn you should carry more speed into it ( the first apex moves earlier ). If you are coming from a very short straight to a very long one, you should convert the double apex into a single late one and do a slow-in/fast out sequence. Because turn 8 divides two long straights, theory says a typical double apex is the norm.
The other variation comes with the type of car. A low HP/high grip car uses the double apex to prevent the lost of momentum at the turn in of a single late apex. A high HP/ lower grip car can be faster in a single late apex because it makes a longer straight and permits more acceleration time.

The braking point depends a lot on what you are driving. How much does it weigh? How firm is your suspension? etc. A heavy street car is going to have to brake a lot earlier than a light race car.

Where exactly I brake is a good question. I don't remember. I brake when I feel it's time to brake. I don't really use reference points. "Use the Force Luke"...

I personally try to brake as little as possible. I get on the brakes relatively early but don't use a lot of pressure. I also leave a fair bit to the end so I can trail brake to rotate the car. The only time I go deep and brake late is if I'm trying hard to pass someone fast.

Braking lighter and longer keeps the car as stable as possible - especially in a street car. The more stable the car, the more speed you can carry.

Also, by braking late and hard you often brake too much. It's hard to modulate the brakes when you are standing on them. Brushing the brake over a longer distance makes it easier to control your deceleration. If you can make a corner easier, you can carry more speed.

Jean Luc: where did you find this theory? I'd like to read it. Thanks! John

Two years ago I started doing something completely different - I would aim diagonally across the track and brake right into a first apex, then fade out into the track a little, and turn in for a second apex. Braking along the left of the track then turning in seems like such a waste of time and distance. Seemed to work for me.

Try " Going faster "
Skip Barber

The old parabolic arc. We should plug that into the data logger and see what happens. I can see with your extra horsepower how that would work.

The famous last word: Exit speed.....

Allan's line is a variant on double apex, and the consensus at Lime Rock's big bend and an alternate at NHMS turn 1 into the chicane. An issue I had with this line at NHMS was that I'd turn in from the right to brake up to the apex, but the car would be rocking from side to side because of the more or less violent turn towards the early apex. With the car rocking, the brakes didn't really work (at least not on both sides at once).

To avoid this issue, would you just make a more gentle transition from outside to pointed at early apex? Turn the whole thing into a giant cheat in?

Yes. That's what it says in the text books. But in the real world I find that smoothness usually wins over theory.

To be fast you have to be unbelievably smooth. The smoothest guy will get the most from the equipment.

Accelerating hard into the corner and standing on the brakes has two negative effects.

Firstly, it unsettles the car.

If the car is bouncing around entering a corner, you are going to have spikes in grip that exceed the tires capability. This leads to over driving the car. The only way to avoid this is to go slower. If you are smooth, there are no spikes in grip and you can carry more speed.

Secondly, and more importantly, it's easier.

If you brake hard over a short distance, it is very difficult to modulate how much braking you do. You risk braking too much and over slowing the car. Or you don't brake enough and over drive the corner.

Brushing the brake over a longer distance makes it very easy to modulate your speed. So it's easy to get the corner entry speed just right every time. This leads to smoothness and consistency. Being smooth and consistent reduces the anxiety of racing substantially. You are relaxed and brain can do it's job.

Overall... If you can make a corner easier, you will probably be able to go faster.

The exception to this is in overtaking. To overtake a fast car you have to accellerate as long as possible and brake as late as possible. However, the goal here is not to carry the most speed in the corner. The goal is to get into the corner first so that you ruin your competitor's exit.

I don't mean that you should dive-bomb into corners. That's just stupid. And dangerous. I mean get along side of him in the brake zone so he can not take an efficient line through the corner. Then you will carry more speed relative to him and win the corner.

(Disclaimer, I'm not super fast)
Lately, I've been easing into and then -really- standing on the brakes a little bit earlier than I might really have to, and then backing off very gradually so that the car doesn't bounce around. I can use this backing off phase to modulate speed and generally feel relaxed about my corner entry. The backing off phase includes some trail braking, again with super gentle off so the car doesn't bounce. I try to give the car some time to lean in to the corner too so that there isn't bouncing from entry. Bounce is an issue I'm working on w.r.t. early apex where you turn in, straighten out, brake, turn in again. The first turnin is generating bounce and nothing really works after that. I'm not sure what to do other than to move the first apex so early that the first turnin is shallow enough to avoid the bounce.

Whatever feels right!