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Old 07-24-2018, 07:40 AM   #1
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faster through corners

so, working on my left foot braking. working on my trail braking. want to start thinking about some stuff topless has been saying about 'braking with the steering wheel"; ie, that turning in and of itself will slow the car. i understand the concept, but wondering about application - presume a slower corner technique - chuck your car and get it to rotate early?
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Old 07-24-2018, 01:25 PM   #2
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I was hoping someone would reply by now because I am curious too.

In some slower corners, I brake to set the nose down (and lose a little speed) and then pitch the car around and get back to full throttle, but it only seems to be on certain slower corners, almost like a mental thing (since I only do it at certain tracks but not others, even when the corners have approximately the same speeds) Edit: I think I a thinking of "turn with the brakes" here.

In other corners, mostly faster corners, I have started turning in just a little earlier as I am trailing off the brakes and let the turned wheels slow the car as I make my way down to the apex. Edit: I am thinking of scrubbing off speed with steering here.

I bet neither of these is what he was saying, so I am curious to see what others have to say on it.

Good thread, I hope it gets a lot of responses.

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Old 07-24-2018, 02:46 PM   #3
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Not quite sure I'm understanding the concept. I also think a lot has to do with car setup as well. They way my car is setup - there are few turns where I need to trail brake to get the car to rotate. I'm running a non square setup with 245/275 (250/280 when running slicks) - but also with slightly taller rear tires like the cup cars run.

As for using the steering to "brake" the car - that's really and issue of using understeering to your advantage I would think. Again I would think that car setup would affect that.

To me the biggest issue with this car is the balance between turn-in and getting back on throttle. Too early and it can be a handful. Too late and momentum is gone.

Interested to hear everyone's thoughts as well.
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Old 07-24-2018, 04:46 PM   #4
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Originally Posted by The Radium King View Post
want to start thinking about some stuff topless has been saying about 'braking with the steering wheel"; ie, that turning in and of itself will slow the car. i understand the concept, but wondering about application - presume a slower corner technique - chuck your car and get it to rotate early?
This was a hard technique for me to master since it required a bit of balls and I often find that mine are far too small for the task at hand.

The technique consists of entering the corner slightly faster than normal. This is the ballsy part because your brain will be saying, "Dude, this is way too fast". As you start to turn the wheel, the tires will start to slide since the car is entering too fast. The key is to let the tires slide and scrub speed for a couple of moments without adding any more wheel. Once the car has slowed to the normal speed for the corner, continue turning in and get back on the throttle to balance the car and proceed through the turn.

If you don't pause putting wheel in at turn in (for just a couple of moments), you will find that the car is going too fast and will usually want to spin around. This is where your car handling skill will be tested. The goal is to momentarily hold a controlled slide at turn in to scrub the speed.

When done properly, you can use the tires to scrub some speed at turn in, then do an somewhat abrupt lift of the throttle which will unload the rear tires, then turn hard to rotate the car (aka slide the rear around), and then go hard back onto the throttle in mid-corner to get the weight/grip back on the rear and then start to unwind the wheel and power out of the corner on exit. This is the dreaded mid-corner lift that puts 911 drivers into the wall but works well in a mid-engined car to "point and shoot".

This technique works well for me on high speed sweepers allowing a bit of gain on a competitor at corner entry since he is braking more and earlier than me. It also works pretty well on tight technical corners where you want the car to rotate quickly without having to spend a lot of time going from throttle to brake and back to throttle. On a slower technical corner, you may not have to brake at all, just turn in, scrub, lift throttle, rotate, unwind the wheel and power out.

This is somewhat (but not entirely) different than chucking the car into the corner and hoping for the best. Yes, you're kind of chucking it in there but with a plan for a controlled momentary slide and then transitioning back to normal cornering.

I'll see if I can find an in-car video where I did this well and post it.
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Old 07-24-2018, 05:31 PM   #5
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cool beans - so you're intenionally understeering to scrub speed, then lift throttle to unload the rear/weight the front and rotate. or, presumably, a dab of brake if already off the throttle. that's a balls-out move in a fast corner.
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Old 07-24-2018, 06:49 PM   #6
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I'll see if I can find an in-car video where I did this well and post it.
Try this one, (me) at about :09 seconds.
https://m.youtube.com/watch?feature=youtu.be&v=qn8gJrx2gVc

I think this is what you're describing?

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Old 07-24-2018, 06:56 PM   #7
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If you are using understeer to slow the car into a turn, you are probably braking too early. Generally speaking, if you are "coasting", time is being wasted. In an ideal world, you are either braking, or accelerating. Granted, we don't live in an ideal world, but either you should be either using steady throttle or accelerating through a turn.

At recent track day an intermediate group driver asked to ride with me after he had car trouble. After the session, he told me that there was a BIG difference in the driving level between intermediate and advanced, to him the thing that really stood out was that I was never coasting, I was either on the brake or the throttle. It took me a few years of racing 10 to 12 times in a season to get to the point where I was able to drive like that! It takes track time to work up to that, so practice, practice, practice.
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Old 07-25-2018, 04:51 AM   #8
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This was a hard technique for me to master since it required a bit of balls and I often find that mine are far too small for the task at hand.

The technique consists of entering the corner slightly faster than normal. This is the ballsy part because your brain will be saying, "Dude, this is way too fast". As you start to turn the wheel, the tires will start to slide since the car is entering too fast. The key is to let the tires slide and scrub speed for a couple of moments without adding any more wheel. Once the car has slowed to the normal speed for the corner, continue turning in and get back on the throttle to balance the car and proceed through the turn.

If you don't pause putting wheel in at turn in (for just a couple of moments), you will find that the car is going too fast and will usually want to spin around. This is where your car handling skill will be tested. The goal is to momentarily hold a controlled slide at turn in to scrub the speed.

When done properly, you can use the tires to scrub some speed at turn in, then do an somewhat abrupt lift of the throttle which will unload the rear tires, then turn hard to rotate the car (aka slide the rear around), and then go hard back onto the throttle in mid-corner to get the weight/grip back on the rear and then start to unwind the wheel and power out of the corner on exit. This is the dreaded mid-corner lift that puts 911 drivers into the wall but works well in a mid-engined car to "point and shoot".

This technique works well for me on high speed sweepers allowing a bit of gain on a competitor at corner entry since he is braking more and earlier than me. It also works pretty well on tight technical corners where you want the car to rotate quickly without having to spend a lot of time going from throttle to brake and back to throttle. On a slower technical corner, you may not have to brake at all, just turn in, scrub, lift throttle, rotate, unwind the wheel and power out.

This is somewhat (but not entirely) different than chucking the car into the corner and hoping for the best. Yes, you're kind of chucking it in there but with a plan for a controlled momentary slide and then transitioning back to normal cornering.

I'll see if I can find an in-car video where I did this well and post it.
Are you saying that all braking is done prior to turn in (albeit slightly faster than normal) and that you still have partial throttle that you keep and only lift throttle to rotate the car prior to re-applying full throttle? That would mean left foot braking?
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Old 07-26-2018, 05:54 AM   #9
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As an instructor I’m gonna disagree with the understeer approach. The most effective way to slow your car is with the brakes and 0 or minimal tire slippage. Understeering will compromise your braking and your turn in (kinetic vs, static friction) and will very quickly overheat your tires which will further compromise braking and effect handling.


Here's a helpful way to think about drip. The amount of grip is represented the outside of the circle (the adhesion limit). You can use this grip for accelerating, turning or braking. If you are turning and braking, or turning and accelerating the amount of grip you have will be split between these two functions. For a turn at the end of the straight away you want to start with all your grip being invested into the braking (which means your wheels will be as straight as possible), if your wheel is turned at all you'll be using some grip for turning. As you enter the turn you'll start to lift off the brake and turn in, your tires will still be at the adhesion limit but you'll slowly give more and more grip to turning and less to braking (this is called trail braking). As you accelerate out its the exact opposite, you'll invest more and more drip to accelerating and less to turning as you open up the wheel out of the corner. If your tires slides at all this adhesion limit (or circle) becomes smaller and smaller and you have less grip to use for braking, accelerating and turning.

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Old 07-26-2018, 06:49 AM   #10
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well ...

it's not coasting, and understeer is not an indicator of entering the corner too slow.

i've always been taught that throttle steer (lifting throttle to get the car to rotate) is not the fastest way through a corner as it requires ... lifting the throttle. it's a good technique to know if you find yourself in an understeer situation, however.

further, i agree that pushing your tires like that is not the best way to ensure they last for a 20 minute sprint.

however, i think there is merit in the concept of using understeer to slow the car. i think, perhaps, there is a need to drill down into it a bit more - is it a fast corner technique (vs trail braking, which is more of a slow corner technique) is it a late apex technique (where you can enter the corner faster, turn later, and use the understeer technique to quickly rotate and exit) is it a light car technique (less wear on tires) is it an underpowered car technique (makes me think of the rx7 challenge car guys that run at our track - they don't brake - ever).

i know that, in examining my lat-g through corners, that i can hit well over 1 g at apex and past, but i'm not there at turn-in. the concept of going in with the intent of understeering (and, i presume, aiming inside the apex) might get my lat-g's up earlier into the turn.

where trail braking is a technique to get the rear tires to the limit of slip earlier, this technique seems to be a way to get the front tires to the limit of slip earlier, and combining the two in some way might be the ultimate goal.

edit to add - perhaps there is also a semantic issue here - i'm not sure we are talking a complete loss of traction and exceeding the slip angle, but rather pushing the slip angle to it's limit such that there is maximum slip but no actual breaking free of the tires.

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Old 07-26-2018, 07:35 AM   #11
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If you have time to use understeer to slow the car enough to make the corner, you are wasting time.
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Old 07-26-2018, 12:11 PM   #12
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By far brakes are the most efficient way to slow a car, and an added benefit is that you get a weight shift to the front to help you with the turn. The point of trail braking is to maintain the weight shift. Using understeer to slow the car down also overheats your front tires as they scrub.
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Old 09-13-2018, 06:46 PM   #13
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As an instructor Iím gonna disagree with the understeer approach. The most effective way to slow your car is with the brakes and 0 or minimal tire slippage. Understeering will compromise your braking and your turn in (kinetic vs, static friction) and will very quickly overheat your tires which will further compromise braking and effect handling.
I could not agree more.
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Old 09-13-2018, 09:41 PM   #14
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Hmmm, my ears were burning and after reading this thread I think some ideas may have been twisted around a bit. I don't know where the original reference to driving technique is but I'll attempt to illustrate my method of "faster through the corners".

Cars always accelerate faster in a straight line. They also stop better in a straight line. The fastest way around a track is taking the corners out of the corners as much as possible because whenever the tires are side loaded, you are scrubbing speed and going slower.

Type 1: The most common 90*ish turn benefits from a late apex where you brake in a straight line, perform a quick turn-in so you can immediately go to the gas as you unwind the wheel. Under ideal conditions you will be at full throttle and unwound at the apex effectively lengthening the straightaway under acceleration. The longer you are on the gas in a straight line, the faster you go around the track.

Type 2: On some corners like a 180* or a banked 160* a type 1 turn is the safe play but a double apex is faster. On a right hand banked 160* I prefer to approach on the far left, turn in early with no braking yet, run a straight line to the top of the bank braking very late and rotating the car quickly in a controlled slide. Once it is pointing to my exit I unwind the wheel as I roll on the gas, being full throttle at the 2nd apex. This cannot work in every corner and it carries more risk if you get it wrong, but it can be very effective because it lengthens the straight both on entry and exit, minimizing side loading the tires, and maximizing time on the throttle in a straight line. Practice this one where there are no walls or obstructions to hit if you get it wrong.

This guy demonstrates both techniques here while keeping the car absolutely at the limit of grip in every corner:
https://www.youtube.com/watch?v=fLCpHnA54cQ
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Old 09-14-2018, 06:08 AM   #15
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I believe that originally the discussion may have been around consideration of the steering wheel as a brake mechanism and throttle pedal as a steering mechanism.....please correct me if I am wrong.

Wheels turned = slower pace
Modulate throttle to adjust lines rather than saw at the wheel

.....not that I can do it
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Old 09-14-2018, 07:30 AM   #16
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i know that, in examining my lat-g through corners, that i can hit well over 1 g at apex and past, but i'm not there at turn-in. the concept of going in with the intent of understeering (and, i presume, aiming inside the apex) might get my lat-g's up earlier into the turn.
I am similar, in that I am often at 1+ lateral G at the Apex, but I'm not anywhere near -1 lat G at turn in. However, if I look at my GSUM (combined lateral and longitudinal Gs) it shows how I am combining my braking and turning forces at corner entry.

GSUM = sqrt((LatAcc^2)+(LonAcc^2))

This helps me to see if I am effectively combining my braking and turning at the start of a corner - if it is really low then I might be braking too soon and then gently rolling into the corner at less than the speed at which I could.

In corners where I do a soft(er) brake, like T1 at Road Atlanta, T1 at Sebring, or T1 at Roebling, this is an area where I probably lose a lot of time, as I am way under the limit there. I am driving down to Sebring later today with a goal in mind: "Roll more speed into T1" - I bet I can probably gain a second there just from that change...
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