How To Brake?
 

Here are two schools of thought exemplified by two different "experts" (IMHO) on the topic (excerpts taken from Racer University):

Neil Roberts writes:

"Everyone will tell you that smooth is fast, but there is one exception. The power-to-braking transition at the beginning of a straight-line braking zone can and should be as abrupt as you can manage. That is how to make a pass stick and it is worth a little bit of lap time, so you want to slam the brakes on at the beginning of every straight braking zone. Of course the brakes had better be warmed up first."

Peter Krause writes:

"Jim Myers, my coach, forced me to move away from being seduced by the sensation of doing something special by "slamming" on the brakes. He refocused my attention towards "squeezing" ON the brakes earlier and, more importantly, focused me on where and how soon I could get OFF the brakes. This reduced my natural tendency to over-brake for the corner and allowed me to become comfortable introducing the slight instability required in order to begin the rotation of the car. This leads to the next phase, how to integrate the end of braking into helping the car to begin turning into the corner."

And Neil Roberts closes his views with:

"Most cars can decelerate harder than they can corner or accelerate. That’s why it takes highly developed skills to avoid braking more than you absolutely have to. As your skills and brake system tuning improve, you will find that you use the brakes harder, but for less time and distance in each braking zone. Mastering the art of deceleration is tough to do, but it is highly satisfying, and it adds to your on-track safety by enhancing your contact avoidance skills."

With all due to respect to Mr. Roberts, I am in Peter's camp on squeezing the brakes, especially during the initial application and modulating them through the whole braking zone and trailing as best as I can.


What say you all? Which technique, in general, do you subscribe to?

Re: How To Brake?
 

Slamming;

- Hitting the brake with your foot flying through the air on the way down?
- Getting on the brake pedal hard straight into ABS, but no air involved?

Braking is an art, certainly no expert opinion here, but I would think slamming staight into ABS (Without air) can only work in the beginning of a brake zone that is straight and gives you some time for the car to settle as you are starting to trail brake.

Or maybe where a quick stab is needed to scrub of some speed in a straight line...

I'm with Peter Krause, my laptime is mostly about how early I can get off the brake smoothly and on throttle smootly and quickly... If I can plop down the throttle I know I lost the lap.

Re: How To Brake?
 

They taught Neil's approach at the Porsche driving school. But I've had more success with Peter's approach. Acutally somewhere in between......

Simple goal for me is to figure out how much speed I can carry into a corner. So on a corner that I am not familar with or struggling, I will brake earlier and lighter feeling my way into the corner. After I've got a sense of the momentun I can carry in, I will work on moving up the intial brake application.

Re: How To Brake?
 

I'd agree more with Neil's approach. I think the problem is the semantics of "slamming" the brakes. Peter's approach does have merit. But the merit is learning where to find the limit is. It is NOT the faster approach. Brake like that and you are going to get passed in every brake zone by the competition.

My approach is to brake as deep as possible and then "slam" on the brakes. The semantics of slamming should be.....get to threshold as quickly as possible.

As has been said, braking is an art and very hard to master. Some people just have a very good feel of the physics of weight transfer, brake threshold, etc..

I have NEVER got into ABS in my car. By understanding what creates the ABS situation you can understand how to take it to the razor thin edge and stay there.

Back to my style. When I slam to threshold I immediately start modulating the brake pressure to keep the stopping right at the threshold (ABS) limit. If you are not at the limit you are not maximizing your brakes and thus not grabbing all those tenths laying around the track. Your goal should be to transition from brake to throttle just after corner entry. This method allows you to maximize front end grip and to TB into the corner which results in the need for LESS steering angle and allows you to get on the throttle sooner. Again, picking up tenths all over the place. I heard a quote from Jackie Stewart once. He said that the brake and throttle were ON/OFF switches working as a single switch. You are either on brake or throttle. Coasting is the enemy of lap times and weight transfer. If there is a time gap between brake and throttle or throttle and brake you are carrying too much speed into the corner or coasting. Not good.

If you ever get to watch an F1 practice live (TV is ok but not nearly as info packed) set yourself up at a high speed straight to tight corner transition. You will think that they all forgot how to drive. Why? They are sliding off the track left and right. Their is a method to their madness. They are trying to find both the perfect brake point for transition to corner entry as well as just how much they can bite off past that perfect spot should they need to "make a move".

The problem I see is most DE guys spend the entire session trying to set personal best times instead of setting sector or turn best times. I set out a goal for a specific sector or turn and work on it at the expense of total lap time. Then data analysis tells me what works and what doesn't. Once you truly understand what works ALL THE WAY AROUND THE TRACK then you can start putting it all together.

This doesn't mean you have to work on a section all the time. Some of the best sessions are had by just running with your buddies!

Re: How To Brake?
 

Dell do you by any chance have data that shows the time frame between coming off throttle and max LongG readings. I'd love to be able to quantify what "slamming the brakes" is.

Re: How To Brake?
 

+1, I'm taking notes here!

Re: How To Brake?
 

Let me see what I have and post back.

Re: How To Brake?
 

I'm with Peter Krause. From memory it was Sir Stirling Moss who said that the hardest thing he had to learn in racing was how to take his foot of the brake. Focusing on that certainly helped me improve lap times when I was stuck in a rut. But with the caveat that once you figure out how to take the foot off, then you can start focusing on how to engage the brake - i.e. later and harder.

Early on I used to focus more on the foot-on part, but to the detriment of my corner entry and speed. Through data analysis I finally figured out that's were I was loosing speed vs. my co-drivers.

I haven't driven much for the last 5 years, so now I'm back to developing my sensitivity to the foot-off transition.

-Christian

Re: How To Brake?
 

I have to admit, my weakest point is how and when I come off the brakes, for the past 6 years I have been improving, but that is still the one biggest issue I have.

Re: How To Brake?
 

Here's another opinion, from Vic Elfords 'Porsche High Performance Driving Handbook':

"In the last chapter we saw how important smoothness is in accelerating. If anything, smoothness is even more important when it comes to braking at the limit......."

Then later,

"Although I have emphasized the importance of smoothness, here is one time when you need an abrupt little stab or jab. When your foot goes to the brake pedal the first moment should be just that - a little jab at about 4 on the scale above.

That little jab will take up the pressure in the braking system and cause an instant weight transfer toward the front wheels. As soon as that's done you can start squeezing on the pedal in earnest."

Re: How To Brake?
 

I've only been doing DE's for 4 years so I'm no expert. I do know that when I began I would slam on my brakes and brake more than I had to. One of my instructors worked with me on braking and got me to squeeze on the brake pedal firmly at the beginning of the brake zone and to ease out of heavy braking in order to concentrate on carrying more speed into the corner entry.

One thing I have learned about driving, it's like an onion. As you progress and get a feel for a skill, you peel a layer of experience off, and that reveals the next layer that you must concentrate on to master.

Re: How To Brake?
 

I was always taught, and in turn taught my students, that the best way to apply the brakes (in a straight braking zone) was to squeeze them at first in order to get the car to squat for best stability, then hammer them to threshold, gently easing off as you transition to throttle. The trick is to do all this in the least possible amount of time. I've yet to feel I've truly mastered this technique in my 15 years of DE driving!

Re: How To Brake?
 

Here is a theory:

I've recently perused a PDF about the physics of racing, and while it gets a little too involved in the equations for my (MIT educated) brain, it does have some interesting conclusions and corollaries. For example in the chapter on why smoothness is important, we learn that given the car and it's suspension is really a spring/mass/damper system it likes sinusoidal inputs.

Hmm, I've always known that smoothness is important, but I never really thought that smooth doesn't necessarily mean linear! So I've been experimenting with doing sinusoidal-ish steering inputs, i.e. start of slowly and then accelerate the input to quite quick and slowing it down again as I reach full lock. Its quite amazing. If you have a heavier car with a soft suspension try this. With my wife's Prius if I do simple linear input going somewhat swiftly into a turn, it leans out of the turn and almost feels like it's going to topple over - despite being smooth about it. If I try the sinusoidal input instead, it's completely different! It kind of squats down, almost leans into the turn and is far more stable. Wow!

I have yet to try this on track, but I image that the GT3's relatively stiff suspension and stiffer low profile tires will make the effect less noticeable. It'll be interesting to see.

Now back to our regularly scheduled programming.

I'm wondering if braking isn't the same thing. It would certainly explain variations on the theme that one should start by a softer application of the brakes to get the car to settle before squeezing harder. Similarly the idea of getting off the brakes in a more gentle fashion after a hard application. In fact if you combine these two you get: first soft on, then hard, then soft off. It's basically sinusoidal!

Something to ponder.

-Christian

Re: How To Brake?
 

Good points Christian. Although I understand your points, IMO "smoothness" is not being smooth with your inputs but with the resultant behaviour of the car. Most pro drivers we see driving seem to have very jerky steering and other inputs, but as long as their actions result in smooth weight transfer through out the car, that is all that matters.

Re: How To Brake?
 

It depends on what kind of corner it is, but in every instance, your first hit on the brakes should be your hardest, then you modulate as necessary. For tight corners being approached at high speed, that initial hit might be 80-90% or even all the way to threshold... for sweepers, this initial hit might be 25-30% or even just a brush, and longer duration. There are other factors that come into play as far as how much braking is needed - going uphill? Less braking is needed than you might think... long sweeper? The friction of the tires being being turned for that long of a time will help slow the car down, so don't over-slow the car on entry... I see a lot of people over-slowing their car for sweepers. BTW, threshold is not getting into the ABS, it's just short of it - without ABS, it's just short of lock-up.

But, the most important thing is you want to scrub-off speed of the mass of the car, but not kill your momentum doing so. In all cases, you want to use the modulation of the brakes to get the car settled back down onto the rear axle some - a good 10 feet or so - before turn in, so the car is balanced when you begin to turn the wheel for the corner. So many people concentrate on very late braking and corner entry speed, with most of the car's weight still on its nose as they turn in, which kills momentum. I see and coach many very late brakers who find themselves "parked" in the turn, having broken their momentum with this style of driving. Having the car more balanced at turn-in allows you to use super-light braking for balance, or trail-braking for rotation on the way to the apex, and a balanced car at the apex allows you to carry momentum through the corner, and get on the gas sooner as you exit. You can't get on the throttle early with a poorly balanced car. It's corner exit speed, not entrance speed, that makes the difference in gaining those tenths that are laying around the track waiting to be taken. The sensation of entering a corner fast can fool you into thinking you're making up time there, but you can only carry so much speed through the apex of any turn.

I guess I subscribe to slightly longer, and slightly earlier braking to keep the car more balanced. I used to be - as one of my coaches called it - a "scary late" braker, but I'm much faster doing it this way. My mantra: It's not how fast you go, but how little you slow down.

Re: How To Brake?
 

I disagree - smoothness of inputs directly translates into smoothness of the car on the track. Often what you're seeing with in-car camera on pro drivers is them being constantly on the knife-edge - they are moving the wheel to make fast corrections that are necessary to keep the car on the road. Emulating this style while not having to make corrections because of understeer or oversteer conditions just wears out your arms and tires.

Re: How To Brake?
 

I too fall more into the "ramp up the brake pressure" rather than the "hit it hard" technique, but for a few as yet unmentioned reasons. First, if you've ever driven an non-ABS car, you will appreciate the additional rear brake bias that you can run when you don't initially pitch the car on it's nose. Secondly, how "fast" you can actually ramp up the pressure depends on how stiff your car is. With a softer suspension like a stock GT3 has, you have to allow time (a few milli-seconds) for the front to dive under initial application. This will prevent excessive pitching and actually allow for greater initial braking. Even with full race suspensions, I have found it better to squeeze on the brakes rather than just pound on them. The more evenly you can keep pressure on all 4 tires the more grip that you will have, and the harder you can brake.

Re: How To Brake?
 

Let me put it in another way. I define smoothness as getting the weight transfer to any part of the car as fast as possible just at the right time it is needed while staying on the optimum tire slip angles. To achieve this smoothness of inputs are irrelevant, actually abrupt inputs sometimes (or may be even often) are welcome. I am of course only stating opinion here and my understanding on how the theory should be translated into practice.

For example, we see pro drivers with very abrupt steering and throttle inputs, not to mention how they use the brakes. Nothing I see in vids can be classified as "smooth" driving from the input perspective.

So, if you are in a corner with increasing lateral Gs, which increases lateral weight transfer and vertical and lateral loads on tires, the slip angles of the tires will change and that change is constant. To manage to stay at the optimum slip angles that generate the most grip, you have to modulate steering and throttle constantly as well. That is why we see such rapid and abrupt steering inputs.

Similarly, the harder you accelerate, the more abrupt the throttle, when you lift off, the more weight will transfer to the front at a faster speed. If you do execute this at the right moment, the less brake you'll need to use. But again the input is not smooth, but the resultant action creates higher grip when needed and smoother output.

Of course this is all in my very humble interpretation of car dynamics and driving theories. :)

Re: How To Brake?
 

^
Sprint racing you can beat the crap out of the car,

^
Endurance racing you have to be smooth, and preserve the car.

You'd better believe the latter are very smooth with their "inputs", otherwise the race is over early.

I think you need a session or two with Hurley versus some of the curb hoppers.

Re: How To Brake?
 

This is a great discussion. I've always been taught that smoother is faster. An illuminating place to learn about braking and suspension response is on a motorcycle.

Re: How To Brake?
 

I guess I define smoothness as not unnecessarily upsetting the balance of the car. If you were to view the car driven by the pro drivers you mention seeing using very abrupt steering and throttle inputs from the outside, I guarantee you'd see a car that's twitching all over the road, not only side-to-side, and with weight transferring front to back as well. The main reason for not using abrupt steering and throttle inputs (both onto the throttle and coming off of the throttle) is you want to keep the weight transfers even, and as much in one direction as possible. For instance, when you come off the throttle very abruptly as you describe, you not only transfer the weight to the nose, but you can also have the car's front suspension "bounce" back in the other direction, garnering another transfer of weight at precisely the wrong time. The exception to this is when there's a dip or sudden elevation change where you might want to hammer the brakes as the suspension bottoms out to keep the suspension from bouncing on rebound, so the car stays settled. This will depend on how stiff-ly sprung the car is of course, and the rebound settings on the dampers... but in most cars, even race cars, there will some rebound from very abrupt release of the throttle. Side-to-side transfer of weight is the same thing - you only want to transfer weight once, if you can.

Some driving schools (I once heard that Jackie Stewart was a big proponent of this) use a car with a punch bowl bolted to the hood that contains a tennis ball on a string - the objective is to go as fast as you can while keeping the ball in the bowl.

I will say this - many times when you see in-car views of pros racing, they're doing these kinds of inputs because they're not on the line... when I'm doing W2W racing, and making passes, I'm spending a huge amount of time off the line in order to make headway through a lot of slower cars, or just trying to find a way around someone. Driving off the line, and in the klag, might necessitate these kind of inputs, but for fast qualifying laps or time trialing, a smooth transfer of weight, and keeping those transfers to a minimum is much preferable, and ultimately faster in my experience.

Re: How To Brake?
 

Smoother IS faster. What's also faster is keeping the wheel straight for as long as possible as opposed to having some steering input. And having little or to no toe either front or rear (keeps the chassis from binding, putting heat in wheel bearings creating hot spots).

I race laydown karts and road race sprint karts on big tracks, you had better believe steering input slows you down. Chassis setup is paramount for control. We watch everything from scrub radius to alignment almost every practice session- we can gain 1/10sec from more power, but literally a second or two if we can get closer to ideal chassis setup.

Of course all this is for naught if you can't drive... Smooth inputs at all times, smoothly to threshold braking, smoothly on throttle to WOT, smooth steering inputs to get into and out of corners quickly. Just because a car/kart can be darty does not mean that's how it's meant to be driven.

Re: How To Brake?
 

No doubt smooth is faster, but I am putting an argument as to whether the input or output need to be smoother, or are they the same?

Re: How To Brake?
 

Obviously if you stay within the traction circle you won't lose any traction, but to stay within that circle requires you to not exceed the chassis capabilities- those capabilities determine the size of the circle.

Ultimately we are concerned with getting through turns quicker, right? Instead of thinking of turns as brake-throttle input-turn in-track out-more throttle input, concern yourself with how to get to maximum speed as early as possible by track out. That usually means forgetting you have a ton of power, carrying far more speed into and thus out of the corner on a very stable chassis, and using far less brake than you thought you needed. I noticed my car is very neutral if the chassis is balanced, so if I don't give it any input via throttle, brake or steering the car is very settled and predictable. However, giving it throttle will lift the front, reducing the traction circle for the that end, and lifting the throttle will increase it. Braking will cause a more abrupt shift in weight transfer and really reduce the rear traction circle. So, if you are smooth on ALL your inputs you will always be able to maximize the size of the traction circle on the end of the car that needs it most. Now what you do with that traction, and whether you can use it to the limit, is another matter.

Of course, there are instances like in AX that you violate that concept to induce oversteer, but even AX requires a good pointy front end.

I'm sure I'm oversimplifying a lot of my concepts but the gist is there.

Re: How To Brake?
 

I think this is a truly excellent question!

The point of my previous post, which I didn't manage to state very clearly, is as follows: the car being a dynamic system of the spring/mass/damper kind, needs sinusoidal inputs in order to generate linear - i.e. smooth - outputs.

Sinusoidal meaning slowly initially, then accelerating to fairly quick, then decelerating input to the steering, the throttle, and in case of this thread, application to the brake.

I like this theory because it encompasses most of the comments from from different people, and it seems to work in real life too!

-Christian

Re: How To Brake?
 

You bring up a very important point which I often discuss with track newbies. I usually hear them excitedly exclaim that they were driving on the limit. I point out that "the limit" isn't a fixed quantity. A pro driver will drive the exact same car in a way that has a much higher limit. The point of learning how to drive isn't to get to the limit, but rather to first maximize the limit and then push to car to that limit. Which is what you are saying about expanding the traction circle by way of your driving.

The first time I went in a car with a professional racing driver, what was most striking wasn't how "exciting" it was. On the contrary it was how "calm" it all was - despite going incredibly fast. That was the first time I really got an insight into what smooth was, and how important it is to be even more relaxed the faster you go!

-Christian

Re: How To Brake?
 

For what it's worth that is the exact way I have to brake at T1 at Road America. The faster the speed, the more important you don't upset the car, especially if it's bucking like a bronco at 170mph!

Re: How To Brake?
 

Now that I have re-read your original post on this and this post, things are making more sense to me, at least this above statement is the first link, conceptually, between my chassis dynamics and driver training. Previously, I have not been able to link the two together in concept or execution.

My driving experience, as with most that replied to this thread, certainly collaborates this statement. My data also collaborates this statement. The part that is not collaborating or making sense to me is why would some professional drivers that I talked with advice me to be abrupt, especially under braking. The same thing happened during my recent PSDS visit too, which the coaches were in the camp of what Mr. Neil Roberts states.

There is no questions, I put out posts that are argumentative to generate discussion, but at the end I am trying to find out what is the next level of driving I need to be shooting for. I think the answer right now for me is the sinusodial approach (Christian, you should trademark the term "sinusodial driving" :-))) ); keep collecting data and analyze it until I can hit certain lap times while being absolutely smooth with inputs and observing the smooth outputs ::-/

Thank you.

Re: How To Brake?
 

I agree strongly with this! Carrying more speed through and OUT of a corner has much to do with the stability and balance of the chassis, in my experience. Easing of the brake a little earlier than I am comfortable doing, staying CALM, can actually result in a more stable entry resulting in earlier throttle application.

But......how you use the brake to achieve balance seems to vary depending on the corner. I'd love to hear opinions on when you want a flat chassis vs a loaded nose vs early throttle?

For some reason, I developed a bad habit of maintaining some brake pressure on ALL turn in's; a habit of trying to keep the nose down for good grip. But I'm fighting that habit and realiziing I've got to try different things.

T10 at VIR and T12 at Mid Ohio come to mind as examples of where I want straight line braking and off the brake early enough to insure a flat chassis at turn in. Both seem to have some postive camber at first and then flatten near apex.......so does flat apex = flat chassis??? If so, why does T1 at VIR seem to require a lot of trail brake? It has some positive camber on the entry but goes flat near the apex.... I assume it's because you're approaching at high speed, trying to maintain speed at long as possible with a relatively low speed exit? Yes? Or does it have more to do with the radius?

I understand a lot has to do with the car but are there any rules of thumb or opinions on proper chassis attitude relative to track surface (elevation/camber/radius)?

I like this thread, thanks!

Re: How To Brake?
 

That's a function of how large you need the traction circle to be at whichever end you need it at most.

For some corners like at Road America's Carousel, a long sweeping slightly downhill righthander that literally lasts 10 seconds or more, a neutral throttle will help keep the car in shape, a slight lift will tuck the nose back in (gain front traction from moving polar point forward plus camber gain from front end suspension compression that results from caster amount, PLUS a larger tire contact point at the front left wheel), and a slight acceleration will push the front a bit (scrub off lateral force if you've turned in a bit too much).

Again, I'm simplifying it quite a bit, there's a lot more going on- for example, LSD locking/unlocking, the rate at which it locks/unlocks, etc. But for the most part, I think I'm not too far off in concept.


That's the worst thing you could probably do. Don't forget about the traction circle- the more traction you use for braking, the less you'll have for turn in. You may be expanding the circle by getting on the brakes, but the effective turning traction is probably severely limited. You have to ask yourself- which is more important- braking or turning in, and divvy up the circle accordingly.

Brakes on a racecar (or street car on the track) are not for actually stopping- you never want to actually stop. Brakes are for modulating speed- a tool to get the car to behave the way you want it to BEFORE you get to the apex. I've noticed that most people tend to overbrake because they thing threshold braking into corners is the fast way- probably read it in books, but never really properly taught by someone. The function of threshold braking is far more difficult to execute CONSISTENTLY- you may be able to do it 20% of the time, maybe even 70% of the time, but to drive effectively on the track you have to learn to execute each action as close to 100% as possible. Most people I know who threshold brake to the apex (like what they teach in the Skippy books) are incredibly bad at it, tending to overly slow down their cars- you can hear their mistakes when they release the brake and get on the throttle very abruptly. Even the pros make mistakes doing this- every time you see a racecar go straight and miss the apex, the driver is probably fighting braking forces (getting the car slow enough to get within his turning traction circle).

I can't comment on T10 at VIR, it's been many, many years since I raced either course there and never the full course. At Mid Ohio T12 in a kart is a throttle breather- maintenance throttle before turn in and back to WOT before T13. In a car I would say that corner is a bit tricky because of the subtle off cambering of the turn (track falls away from direction of turn). The other thing to note at T12 is you have to give up some of the track out for the turn in for T13, which again you give up some of the track out to get a good run onto T14 and the main straight. If you construct your corner exits taking each turn in reverse you will usually end up with a more ideal line (at least that works for me).

Re: How To Brake?
 

Thanks for the feedback! I am with you on long sweepers and threshold braking.

In my experience, T12 at Mid Ohio is indeed tricky if you hold the brake as you approach the apex. As you describe, the track flatens and falls away but has positive camber on the approach. Keeping the front end loaded with the track falling away equals



For me it's best taken with straight line braking, off early, settle, touch of throttle and all is good.

Can you elborate?

I can't imagine the braking in a kart can compare to a GT car at Mid Ohio but what do you do in Keyhole and Carousel?

I find my chassis has the best balance if I apply LIGHT brake at initial turn in and hold the same pressure half way to 2/3 through the corner.....basically braking and turning together but very gently and with steady arc'd steering. The tough part is in not applying too much initial brake and trusting that I can maintain constant pressure and the car will arc smoothly.

Re: How To Brake?
 

At the Keyhole we go to threshold brake immediately (braking in a straight line after the chicane), then turn in after braking is complete, apexing twice around the turn, riding the concrete patch for the most traction. Throttle application is immediate because the chassis is settled (unlike a car), increasing the throttle as long as the front end stays planted in the right direction (no lifting). Track out to the runout patch on the left, straightline the track from there to the turn in point at T5 (coming across the track near the emergency lane on the right).

The Carousel at M.O. is tricky because of the big bump in the middle of the apex. That tends to separate ribs if you're not careful. We tend to go through T12 hot, flatfoot on the throttle, then brake in a straight line right before the turn in for T13, double apexing it as opposed to a single apex specifically because of the bump. End result is you lose .1 second on that corner, but you keep your ribs intact, and since T14 comes up quickly, the speed you lose through T13 actually helps give you time to set up for T14.

I should be there in two weeks for the WKA National. I can get some on kart footage and post it if you want.

Re: How To Brake?
 

Wow, what a fun looking track with some challenging turns and lots of elevation change. Too bad it's so far from CA!

IMHO the guy lost it primarily because of the brow he was going with too much steering lock on. To make matters worse he seemed to apply the brakes as well.

I was taught to momentarily straighten the steering when going over brows in a turn. It unloads the tires for a moment until the car settles again on the other side of the brow. It's the short version of making it a double apex.

-Christian

Re: How To Brake?
 

NickW, could you comment on the difference between driving karts and cars. It seems that a lot of your racing experience is in karts, but in limited experience with serious karts I found them to be completely different to drive. The main difference being that karts don't really have a suspension, so the weight transfer happens much more quickly than in a car suspension. I was driving kart without a rear differential, so you really had to use the brakes to lift u the inside rear wheel to get the kart to turn in. You pretty much had to do a slight amount of trail braking into most turns.

But I'd love to hear your thought on the differences ihow you have to drive these very different beasts. It's a bit like driving a front wheel drive vs rear wheel drive. You use the throttle with quite different effect in turns. but what about karts vs a Porsche?

-Christian

Re: How To Brake?
 

Christian-

I can probably discuss this on another thread, that is quite a bit off topic and although some of my posts have been on the periphery of the subject, a discussion just on karts and karting dynamics probably isn't appropriate.

There are some things that apply though- my discussion on the traction circle and how it expands/contracts depending upon polar moment and weight bias, etc. The concepts are very similar and in some cases even magnified- you learn very quickly what is and isn't important in setup and driving.

Re: How To Brake?
 

I cannot think of any discussion that is inappropriate for this web forum, except the usual stuff. Discuss all you want please.

Re: How To Brake?
 

I know what you mean! It's pretty nasty in a car and can only imagine how rough it must be in a kart.

Yes, please! I'd like to watch.

It's a blast to drive! I would strongly recommend it for any track junkie. It's also, IMO, a track that will test your braking skills. It requires several techniques; if you want to be quick ;)

Check out the turn before the spin, turn 11. It's exactly the type of turn where you need to open the wheel as you crest a "brow". It's awesome!

I've only been to Mid Ohio twice, most recently last month. It's such a unique and fun track that on my 7 1/2 hour drive home, which is normally a drag, I found myself smiling, seemingly for hours, as I reflected on the weekend. I can't recall ever doing that before :D

Re: How To Brake?
 

The Boxster spins because he/she is braking too hard with too much steering input - too much traction on the front, while the rear has hardly any weight on it. Look at the attitude of the car as it begins to enter the corner - it looks to me the driver thought they were carrying too much speed into the corner, and tried to fix the situation with progressive braking - adding more pressure as they continued to turn the wheel - look at how fast the car with the camera in it catches up to the quickly, and progressively slowing Boxster. Unfortunately the back end also gets light because of the slight crest in the middle of the turn - this exacerbates the situation. but the spin actually begins before the elevation change.

IMHO, one needs to use very different braking techniques for each kind of corner... if you're trying to threshold brake at each corner, no matter it's configuration, then you're using your brakes too much, and probably over-slowing the car in many instances.

Re: How To Brake?
 

Mid Ohio and Grattan are the two most technical tracks in the Upper Midwest and the most fun to drive. I would put either of those up there with Barber, Road Atlanta, and Laguna Seca as technically difficult to master AND fun to drive.

There are other tracks here too within a 4 hour radius (that I have run), GingerMan, Putnam Park, Waterford Hills, Blackhawk Farms, Autobahn Country Club, Mikwaukee Mile etc. but those are either not that fun or not that difficult. There's a little known "favorite track" to some old time F1 and Indycar pros called Meadowdale Raceway that is defunct too. Fun stuff...

Re: How To Brake?
 

With all this discussion, I am pumped up, I am going to VIR again today! :D