07-25-2018, 05:51 AM
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#1
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Registered User
Join Date: Jun 2016
Location: Arizona
Posts: 379
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Quote:
Originally Posted by thstone
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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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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07-26-2018, 06:54 AM
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#2
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Registered User
Join Date: Jul 2011
Location: Richmond, VA (The Fan)
Posts: 978
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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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2003 911 C2
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Last edited by truegearhead; 07-26-2018 at 07:47 AM.
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09-13-2018, 07:46 PM
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#3
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Registered User
Join Date: Feb 2017
Location: NorCal
Posts: 171
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Quote:
Originally Posted by truegearhead
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.
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I could not agree more.
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2001 Boxster 986 (base) #414
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09-13-2018, 10:41 PM
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#4
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Track rat
Join Date: Nov 2006
Location: Southern ID
Posts: 3,701
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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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Last edited by Topless; 09-13-2018 at 11:08 PM.
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09-14-2018, 07:08 AM
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#5
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Registered User
Join Date: Sep 2009
Location: toronto
Posts: 2,668
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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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986 00S
Last edited by jaykay; 09-14-2018 at 07:12 AM.
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