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Trail braking 101

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Old 08-16-2010, 03:36 PM
  #106  
Earlierapex
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Originally Posted by Land Jet
This is one of the biggest current challenges in my turbo combined with having much less experience than most of you. Any tips for focusing and getting a feel for the speed differential between high speed entrance to the braking zone, and corner entrance speed? I'm wondering if I'm slowing too much, although I do experience a lot of push coming out of the 150mph to 50mph corner at Summit Point. My suspension has been upgraded so I'm sure it is the driver.
Start by doing the reverse of everything we've talked about in this thread - back your braking point up by 100 feet and brake 30 to 40% less hard during the first 2/3rds of your straightline braking. This will give you plenty of room and time to focus on your entry speed rather than maximum braking.

Next start to ease off the brakes earlier than normal and look WAY up all the way through the turn. Once you get comfortable carrying more speed into the turn (keep eyes focused WAY ahead, repeat this to yourself 1000 times a lap), then you can move your beginning brake point and brake release point closer and closer to the apex (but not too close, speed in is more important than perfect braking).

And that isn't just "beginner" advice. Schumacher did one thing better than anyone - he hit the brakes earlier and less hard which enabled him to consistently carry more speed into the corner.

Think about how hard it is to hit perfect braking points when you are slamming on the brakes as hard as you can holding on for dear life! Focus on corner entry and the braking will take care of itself.
Old 08-16-2010, 04:07 PM
  #107  
M758
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Originally Posted by Derick Cooper
Think about how hard it is to hit perfect braking points when you are slamming on the brakes as hard as you can holding on for dear life! ....
This is a classic "out braking yourself move". You brake soo deep and so hard to never make the corner since you still try to slow down.

Originally Posted by Derick Cooper
Focus on corner entry and the braking will take care of itself.
Do this well and you will be fast. Braking is not about braking, but about corner entry. Braking on a track is not about who can go the deepest in corner or pull the most G's. It is about getting the car to make corner entry.

Gearing is also important. There are at least 2 corners on the tracks I run where I go much faster taking the corner in a lower gear. 3rd vs 4th. In 4th the engine braking is too small and avaible torque to transfer weight to the rear if case of spin is not enough.

In 3rd I can use less brakes and more engine braking to achieve the weight transfer I need to make the corner. So this is one reason why brakes are not as important as getting the car to make the corner. The brake pedal is tool to do that. Engine RPM is another too. Same to are tires as you can toss a car sideways to help slow it down. If you focus on making the corner entry right rather than max braking you will learn to use all the tools possible to get aroud the corner fast.
Old 08-16-2010, 08:30 PM
  #108  
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It's OK to coast. No really, it's OK....
I know a lot of instructors say things like you're either on the gas or on the brake but coasting can be very beneficial especially in tight, declining radius turns. It allows you to carry more speed into a corner knowing you're going to let the tires work 100% on cornering before before getting back on the throttle. High lockup up diffs like Guard's 50/80 can be used to contribute to rotation while coasting as the outside wheel can't keep up.....
Old 08-23-2010, 08:12 PM
  #109  
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"Braking is not about braking, but about corner entry"

This is so nicely put!

I learned this...and everything about driving hard, the slow way, on the street. Having no money for a fancy car, or driver training, or even any books on the subject, I taught myself. Once I got past the first crash, and realization that I would die if I did not do it right, I learned to find all the relevant lessons at relatively low speeds.

So when I figured out that I should practice driving with the minimum inputs possible, trailing throttle, and trailbraking revealed themselves as my friends. Now I do everything I can to avoid using that circular thing to steer, and do as much of it with the throttle and brakes that smoothness will allow.

I have no idea how well it will translate to the track...has anyone else done things in a similar way, and learned this stuff before ever hitting the track? Does it translate well, as long as you are comfortable with low traction at high speeds?

Now...if I could only get to the track, and see if 18 years of practice in "slow motion" translate well.

Or...win the lottery, buy a superchanged 993 and at that point, I only have to worry about my tires holding up at Flatout speeds...
Old 08-24-2010, 10:34 AM
  #110  
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Originally Posted by Cheyenne
...I have no idea how well it will translate to the track...has anyone else done things in a similar way, and learned this stuff before ever hitting the track? Does it translate well, as long as you are comfortable with low traction at high speeds? ...
I learned alot of car control skills in a parking lot doing autocross. The difference on the track is that due to the greater momentum everything is more delicate. The car responds the same way, but the magnitude of response and inputs are different. Of course the magnitude of mistake is much greater too.
Old 08-24-2010, 09:35 PM
  #111  
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Here is a good comparison from 3 drivers/racers. One car has more power the other 2 are similar hp, but one 150 lbs lighter. The biggest difference is technique in extended turns using what JR called coasting I was taught this as "rolling" into the corner. Entry begins with trailing followed by early apexing and holding on for your life. You cannot get on the throttle early. If you hit it correctly throttle is applied between the apex and track out fully to avoid spinning. Notice the apex speed difference in T1 at the Glen. lap times are: 2:11, 2:12 and 2:08. The 11 and 12 are front running times in their prospective classes. It's hard to believe that the slower top speed car is that much faster overall, but corner speed is critical in average lap speed = eg lap time.
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Old 08-25-2010, 09:01 AM
  #112  
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Excuse my ignorance. Just starting to get into the data logging thing, but are we to read that the green line car is the more powerful/faster one? Therefore assuming that the bottom row is distance and this shows all 3 cars at the same point on the track, just at varying speeds. I think that I'm missing something clearly.
Old 08-25-2010, 09:26 AM
  #113  
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Yes, you are missing something, but understandable. Green car has more power which is seen on the straights. Despite the added power the car is 3 secs a lap slower than the blue trace. Graph is distance versus speed to avoid the blue line getting ahead of the others. Despite being slowed in two corners from DE traffic the blue line (car) is significantly faster than the other two which do now "roll" the car into and out of the apex. They just trail and early power application. If you look at the first turn you will see the min apex speed goes somewhat flat on the blue and over 10mph faster than the other two. This shows up in a couple of other turns along with LFB application into the chicane after the back straight (bus stop).

The hardest development in a drivers skill set is gathering enough entry speed that you cannot apply throttle without the car spinning or wrecking. Throttle becomes a correction at exit to balance the car as the steering opens up. Hardest skill for me to learn and still developing it.
Old 08-25-2010, 11:11 AM
  #114  
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Originally Posted by bobt993
The hardest development in a drivers skill set is gathering enough entry speed that you cannot apply throttle without the car spinning or wrecking. Throttle becomes a correction at exit to balance the car as the steering opens up. Hardest skill for me to learn and still developing it.
Very well said. In order of driver development skill set, I think it usually goes like this:
1) learn a late apex and how to get on the power early
2) learn threshhold braking and trail braking
3) learn corner entry speed and an earlier (but still slightly late) apex

When you start working on 3, you have to "unlearn" some of 1) and 2).

If you aren't terrified BEFORE the apex, you are leaving sips of still cold beer at the bottom of the bottle.
Old 08-25-2010, 11:02 PM
  #115  
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Guys
Old 08-25-2010, 11:20 PM
  #116  
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Faust now you can change your mantra ^^^^^^^^^^^^^^^ "Fast in--hold on--- fast out"
Old 08-25-2010, 11:35 PM
  #117  
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Originally Posted by bobt993
The hardest development in a drivers skill set is gathering enough entry speed that you cannot apply throttle without the car spinning or wrecking. Throttle becomes a correction at exit to balance the car as the steering opens up. Hardest skill for me to learn and still developing it.
Is the throttle stopping rotation, sideways drift, or just getting things ready to accelerate?

I'm stuck in FWD cars, so I'm always having to rotate more than I might otherwise. Or I'm doing it wrong!
Old 08-25-2010, 11:56 PM
  #118  
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Originally Posted by bobt993
Faust now you can change your mantra ^^^^^^^^^^^^^^^ "Fast in--hold on--- fast out"
Yeah, but I'll wait a bit... til I can actually do it, LOL.
Old 08-26-2010, 12:01 AM
  #119  
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Ok, how's this? v v v v v v v v
Old 08-26-2010, 02:30 AM
  #120  
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Originally Posted by bobt993
Yes, you are missing something, but understandable. Green car has more power which is seen on the straights. Despite the added power the car is 3 secs a lap slower than the blue trace. Graph is distance versus speed to avoid the blue line getting ahead of the others. Despite being slowed in two corners from DE traffic the blue line (car) is significantly faster than the other two which do now "roll" the car into and out of the apex. They just trail and early power application. If you look at the first turn you will see the min apex speed goes somewhat flat on the blue and over 10mph faster than the other two. This shows up in a couple of other turns along with LFB application into the chicane after the back straight (bus stop).

The hardest development in a drivers skill set is gathering enough entry speed that you cannot apply throttle without the car spinning or wrecking. Throttle becomes a correction at exit to balance the car as the steering opens up. Hardest skill for me to learn and still developing it.
Yes, I gathered the speed differences but because I couldn't see the times I was confused. So in other words in view that you had just stated the slower car had done the better time we were to take that for granted. Your point being made was that the less powerful car had done the better times and you were just demonstrating the speed differences don't automatically translate into faster lap times?
If that was a distance AND time graph would it show the blue car ahead on the graph as well?


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