Thursday, October 25, 2012

How To Drive NHMS Turn 1 (South Chicane)

After driving NHMS for 10 years, it still amazes me how many drivers (new and advanced alike) drive the outside line for the entry into Turn 1 (South chicane configuration).



Look people, Turn 1 at NHMS is a Type III turn (leading to another turn). Yes, the outside line taken by the 'Vette in this video would give you faster exit speed IF you could carry the speed on the way out of the turn (i.e. if it were a Type I turn). But this is a throwaway turn where you compromise the exit to a series of turns, so you could position the car for fastest exit out of 2b, which leads to a short straightaway. If you cannot carry the speed out of Turn 1, your best option is to shorten the distance traveled going into the turn. Taking the inside line cuts distance traveled by at least 40-50 feet compared to going on the outside.

The only (small) drawback to taking the inside line is that you would have to do more turning in a short amount of time when you get to the turn, best accomplished by using aggressive trail-braking. This is not a skill expected for new students to know. But anyone running in the advanced, instructor and even intermediate group should be taking the inside line. Spread the word, so instructors, classroom, and students can all synch up on this. When executed properly, the inside line is the fast line through NHMS Turn 1 (South chicane configuration).

Related posts:
New Hampshire Motor Speedway: Slippery When Wet

8 comments:

  1. I don't mind the trail breaking, with less of a camber difference between the front and rear wheels it may actually be a more stable speed line as well.

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  2. Just be careful in the wet as trail braking to hard on turn in can induce a spin, as I found out last Friday......

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  3. One of the advantages of yellow group is that I get to make a lot of novice mistakes and as a result get a lot of instructor advice. The outside line has never seemed very efficient to me but the majority instructor opinion is to always take the outside line.

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  4. Yes,Friday was very slippery at NHMS and required more advanced trail braking skills. Taking a tighter line is safer IMO because a spin would not result in a contact with the wall. I'd hate to see a car spin close to the wall!

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  5. I would argue that Turn 1 is a Type II corner - end of straight where entry speed is of most importance. Turn 2A is only important to get you set up to go faster through turn 2B and down the back straight.

    I agree that trailbraking in is important, but the higher (and longer) line provides a much larger radius and allows a higher speed and lower sector times.

    This comes from 2 years worth of data trying the different lines. The fast you go on the high line, with more trailbraking, the faster (time wise) you get through the south infield.

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  6. Matt, the definition of a Type III turn is a turn leading to another turn (a throwaway). Do you really consider Turn 1 to be a Type II corner?

    From Going Faster:
    Brake-Turn vs. Corner Type
    Your decisions about how much brake-turning to do are also affected by whether you"re dealing with a Type I, Type II, or Type III corner. As you no doubt recall from the chapter on the racing line, we said that the line could change depending upon whether a corner led onto a straight, came at the end of a straight, or led to another corner.
    In corners leading onto a straight, exit speed is king. You want to bias the throttle application toward the early side, so you would tend to do a shorter brake-turn in Type I corners.
    In Type II corners where exit speed is not the prime consideration, you could make use of the braking and turning ability of the car and decelerate up to or past the apex, making up time in the braking zone.
    In Type III corners, you are more likely to not only extend the brake-turning zone but to find yourself in situations where the slowing down process will have to begin while the car is still turning.

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  7. PCA guys tend to run the inside far more consistently than BMW, and seems most fast guys, time trialers and racers run inside as well. Running the inside line with others running wide radius creates interesting situations when you start 3 car lengths back and end up 5 feet from their door handle

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  8. 5 feet from the door handle? That would feel like a luxury suite in a race j/k

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