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Trail Braking Q's...

Discussion in 'Racing and Driving Techniques' started by RoughKnight, Jan 13, 2010.

  1. RoughKnight

    RoughKnight Christmas Car

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    So my build has stopped, but I still enjoy driving! :D

    Few questions about trail braking; I've been practicing ever since my last time at the track around open corners on the road, and I just want to know if anybody has any feedback on my technique or where I can improve.

    There is one corner in particular, its full 90 degree turn around a bend, very sharp too, max speed staying just in the outside lane is about 80kph, so my process is...

    Full brake (no lock) until dropped to about 60, then slowly take my LEFT foot off the brake while my RIGHT foot feathers the throttle, then just before the turn brakes are off and i'm about 50%-65% throttle to load the front suspension properly. Then full out after the apex.

    Question, i've only been able to get MAYBE 6-7kph more, one time i've noticed I exited around 87, so my question is:

    After loading the front suspension for the turn, I don't feel the "grip" I think I should be feeling, as there is a little bit of understeer. Does that mean brake more or less throttle?

    Discuss.
  2. RoughKnight

    RoughKnight Christmas Car

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  3. Briansol

    Briansol Admins Admin

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    trail braking is used to rotate you. Basically, you need to be at coast speed already, and in the corner. using a bit of brake and a bit of throttle will fight understeer and give you a little rotation.
  4. TurboMirage

    TurboMirage Finally boostin'

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    In 4-wheel vehicles trail braking pertains to using the brakes past the corner entrance (as opposed to the normally taught practice of releasing the brakes before starting the turn). This practice is used for creating weight transfer towards the front tires, thus increasing their traction and reducing understeer. It works best in light vehicles that have their brake bias to the front.
    In order to be properly performed, the driver must have excellent sense of the vehicle's behavior and be able to keep the braking effort within very tight limits. Excessive braking effort may result in the vehicle heavily understeering, or - if the brake bias is set to nearly neutral - in the rear wheels locking, effectively causing the vehicle to spin as in a handbrake turn.
    Once a driver has mastered trail braking, it can help enter the corners at higher speeds, or avoid an accident if the driver has entered a corner at a speed exceeding the vehicle's (or driver's) capabilities.




    A drift-inducing technique called "the brake drift" is used in racing, involving a series of light trail-braking pulses (usually 2 or 3), followed by a momentary full-force braking and sharp releasing of the brakes. Mastering continuous trail braking as used under road conditions is a prerequisite for learning brake drifting. This is one of the most used drifting techniques in rally racing because - if done properly - allows the driver to enter and exit the corner with full throttle.
    Depending upon cornering situations, techniques like trail braking can be used to maintain more speed upon entry of a corner, and attaining more grip while turning into the corner, and has an effect on apex selection. In this technique, brake pressure is applied slightly later than usual upon deceleration, and is maintained during steering input, sometimes all the way to the apex. The action of braking causes a weight transfer in the vehicle, shifting more weight from the rear of the car forward to the front tires, increasing the normal force on them and in turn increasing the amount of traction the front (steering) wheels have. Because of the characteristics of weight transfer, this technique causes weight to be shifted away from the rear of the car, resulting in lower rear traction, and can be used to induce oversteer in some cases.
  5. awptickes

    awptickes unimpressed by you

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    @turbomirage Yo dawg, I herd u like copypasta, so I put some copypasta in your copypasta.

    @OP You should start to feel how deep you brake, then once you get a better handle on it, like B says, the braking will help you rotate the car.

    Essentially you want to be using 95% of the tire's traction all the time, either accelerating, decelerating, or turning. Without knowing your car's setup, and without driving your car, I can only guess why you're not feeling "the grip [you] think [you] should be feeling." But I think it's because you're braking too much prior to entry. (WARNING: IF YOU KILL YOURSELF TAKING MY ADVICE, YOU CAN'T HOLD ME LIABLE, THIS IS THE INTERNETS, DON'T BELIEVE ANYTHING ON THE INTERNETS)

    Try entering the corner hotter, and braking while in the corner more. This will help rotate you around, get you lined up sooner, so you can get on the gas sooner. Understeer is a condition of the rear tires having more grip than the front, which means you're robbing grip from the front tires doing something. My guess is that you're not braking deep enough, and the weight is being shifted around and off the tires that need the weight.

    Again, without knowing your setup (stock everything?) I can't really help. Without knowing the road surface, I can't help either (Banked corner?) Take what I've given you at your own risk. Read a bunch of books:

    Amazon.com: speed secrets: Books
  6. TurboMirage

    TurboMirage Finally boostin'

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    you should watch some of my autox videos i used to trailbrake all the time... although its actually much faster apexing at the proper speeds and using brake and throttle "percentages", mostly opposite. especially if you have R compounds this becomes key since trail braking FWD cars usually leaves you pointing the wrong direction if you are over zealous

    i tend to brake in a straight line, and as i turn the wheel i let off the brake as to not upset the turning forces of the tires. as i apex, i substitute brake for throttle. same theory works in reverse. the closer you get to straightening out the wheel the more throttle you can apply as to not spin the tires or wash out your grip. by the time my tires are straight i am full throttle.

    make sense?
  7. RoughKnight

    RoughKnight Christmas Car

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    Finally, some answers. Mirage you first post, not so much. Second post was just what I needed to hear. And awp too. I tried it last night, little hotter, and I felt squirmy at the limit, so I need to rejudge my braking.

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