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Discussion Starter #1
So I've read thru all the threads on understeer and still don't have a clear understandig of what I can do from a driving technique standpoint to eliminate understeer. I watched the Top Gear video with Clarkson understeering like a pig and then the Lotus guy drifts around all the same turns but it was never clearly explained. Other threads seem to be giving conflicting advice. (All of the above in hopes of avoiding the "do a search" response).
So...I'm calling out to all you fast guys, Manly, Tim Jack, AJ (sorry, I only know the SoCal hotshoes, the rest know who you are) to give me some help.
For the sake of this discussion, let's assume my settings and tires are right. Lucent in LA set it up for track. For propriatory reasons they've asked me not to post the exact settings but they are within the parameters that most of you experienced guys have suggested (machined control arms, etc). I'm running Toyo r888's 26f 28r hot.
I experience it on both turn in and exit. On Streets Of Willow, turn 3 and the skidpad turn are the worst. I brake hard, turn in hard, get on the gas and the front tires squeal like stuck pigs and I plow to the outside.
Would like to work on this before Buttonwillow next week, so let me hear your thoughts!
 

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Throttle lift on turn in, when it breaks out, nail the gas to pull through.

Worked for me with ao48s and with my new 245 Zeon 2xs tires.
 

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Discussion Starter #3
Throttle lift on turn in, when it breaks out, nail the gas to pull through.

Worked for me with ao48s and with my new 245 Zeon 2xs tires.
So brake (in a straight line, no trail brake), turn in on throttle, THEN lift to redistribute weight to fronts, then reapply throttle?
 

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Thats what I do, works for me. The harder you lift, the more the tail will wag out. Giving it gas pulls you back into line as it catches traction.

Now you could use tail braking to induce the same thing, I personally dont. Id say the left foot brakers would prefer tail braking to lift.
 

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If you have never left foot braked before do not do it around any other cars or turns with curbs or close walls. The left foot is not used to doing this move and the ability to stab the brake to hard (reflex move the left foot is used to hitting the clutch) the first few times is most likely what will happen. Don’t want to hear you got rear ended or slid in to a curb/wall while giving this move a try. This is a sort of a kart way to drive. You will either like it or hate it.

If you have an adjustable sway bar play with it a bit. If you don’t, get one.

Kevin
 

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I brake hard, turn in hard, get on the gas and the front tires squeal like stuck pigs
This is pretty common technique I see when instructing. Try braking a little earlier, and using more throttle to the apex instead of braking in the corner.

Then dance with steering input and throttle. Consider the steering wheel and accelerator pedal as being connected by a string. The more you push the go-fast pedal, the less you can turn the steering wheel.

It is all about friction circle and how much work the tires can do. The front tires can max brake in a straight line, plus you are transferring weight to the front tires. Now if you are turning also, they have to do more. Worst case, imagine the tires cranked over almost 90 degrees. You can't steer under braking.. and you certainly would not be able to steer under throttle.

As you corner, don't just mash the throttle. You can make small adjustments on steady state and corner exit to keep the front tires turned.... in other words, crank over the steering until you feel the understeer start, crank back a tick..... keep doing that. Now feed in the throttle also. More throttle, less steering. But you have to be on a line right? So that forces your hand to some extent with steering... so then you adjust throttle. Use weight transfer to help... a lift or even a tap on the brakes can lighten up the rear and shift the balance to oversteer. The adjustments for throttle and steering should be small, not gross yanks on the wheel.

But all of that fails if you dive in too hot, then crank the wheel over too much.... now you are screwed and will plow. Often people then lift and spin. Massive understeer into massive oversteer. Yeehaw
 

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Discussion Starter #7
I think my problem my be that I'm coming in too hot and am carrying too much speed into the turn, then I'm fvcked.I've gotten pretty good at feathering the throttle after understeer insues to correct for it but I would like to learn to go through the whole turn cleanly. I intuitively don't think lifting and correcting is the fastest/ optimum way through a corner.
Any other thoughts/ techniques people are using?
 

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Exactly. So brake earlier.
 

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^I do 99% of my braking before I turn the wheel, I may tap the brake mid turn(Foot on throttle still) if im too hot.

But, to induce oversteer(Not talking Tokyo drift stuff, just mild oversteer to carry the transition) I simply lift harder when I start my turn in.
 

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The type of understeer you're describing comes from asking "too much" from your front tires... while braking shifts weight forward, increasing the maximum traction available, it also uses up some of that traction for the braking itself. If you're braking at 100% of available traction (threshold braking), you have no traction left over for turning, and if you turn the wheel you will understeer. You must give up some braking in order to turn... the more braking you give up, the more lateral G's you'll have available for turning. If you get off the brakes fairly rapidly (but smoothly), you'll still have weight transfer over the front wheels, and you'll have all that traction available for turning. Note that as the front springs unload, you'll shift weight to the back, and start to lose available traction. If you add throttle, you'll shift even more weight to the back and have even less traction available at the front, and if you don't unwind the wheel you'll go back to understeer.

Oh yeah, and what they said ^^^.
 

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Discussion Starter #11
... Note that as the front springs unload, you'll shift weight to the back, and start to lose available traction. If you add throttle, you'll shift even more weight to the back and have even less traction available at the front, and if you don't unwind the wheel you'll go back to understeer.
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Right, so how do i best mitigate this so as to keep as much weight as possible (as a result of braking) to remain over the front wheels? Is it throttle input? After braking, rather than "stepping on it" would "easing" the throttle back on keep more of the weight up front?
 

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Right, so how do i best mitigate this so as to keep as much weight as possible (as a result of braking) to remain over the front wheels? Is it throttle input? After braking, rather than "stepping on it" would "easing" the throttle back on keep more of the weight up front?
^Thats what im referring to when I say LIFT.
 

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A great place to get some of that "brake hard in a straight line, turn in hard, get off/on the gas as the back steps out just a bit to line up the exit out of the corner" stuff (how's that for a short description? rotfl) is a good high-speed karting track.

We have a killer eight tenths of a mile outdoor track in Denver with lots of elevation change and superb curbing that gives you a nice place to practice the physics of it all. Lift throttle oversteer, under control, is a great car control technique!

Tom
 

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Right, so how do i best mitigate this so as to keep as much weight as possible (as a result of braking) to remain over the front wheels? Is it throttle input? After braking, rather than "stepping on it" would "easing" the throttle back on keep more of the weight up front?
^Thats what im referring to when I say LIFT.
Exactly... if you start to understeer as you're adding throttle, either reduce throttle or unwind the wheel... if you can't unwind the wheel (running out of road), then you've got to lift (smoothly please!).

To avoid the understeer in the first place, make your transitions from braking to turning to throttle smooth and continuous... especially on high speed sweepers.
 

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I think my problem my be that I'm coming in too hot and am carrying too much speed into the turn, then I'm fvcked.I've gotten pretty good at feathering the throttle after understeer insues to correct for it but I would like to learn to go through the whole turn cleanly. I intuitively don't think lifting and correcting is the fastest/ optimum way through a corner.
Any other thoughts/ techniques people are using?
Few people (other than those with great innate talent) don't do this, it's entirely normal. We all tend to think "it's better to be going as fast as possible" and put that in the NOW rather than in the LATER :)

By that I mean (IMO) instinct is poor for judging how well you can exit the corner a few moments from now. Instead, it focuses on your speed of the moment and leads you to cornering quickly, but with no drive at the exit.

Just remember, "he who gets on the power first, wins" :)

Steve
 

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+1

Exit speed is almost always more important than entry speed.
Its being able to maximize both that will put you in the winners circle. Most of us are doing HPDE, and there is no winners circle, but its nice to be able to go around the corner as fast as you can safely.
 

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i am a hack - but here are few quick thoughts...

there is more than one way to induce oversteer... you don't want to induce oversteer though, you don't want to "kick out the rear and drift" i mean, its fun though!

you want to utilize the mid engine layout to maintain balance (front and rear grip reasonably equal) through the corner.

so - brake a little earlier, and balance the car at entry with some balance throttle to good amount / to full throttle at apex to track out exit (roughly speaking, randy's sting example, as you unwind add throttle eqaully - assuming you are eqaully balanced to begin with :) ). if you turn in dead with too much momentum, it will plow - in a way, thats a good thing. its telling you "don't do that" and of course you can tune that amount (or the range of difference between under and oversteer - twitchyness) in or out to suit you. that little bit of time at turn in has not much value, you want to exit as fast as possible, not enter per levins comments.

personally, i don't think the car suffers from understeer. i think i have at times suffered from driving like a dolt though....
 

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+100:shift:
Few people (other than those with great innate talent) don't do this, it's entirely normal. We all tend to think "it's better to be going as fast as possible" and put that in the NOW rather than in the LATER
Exactly. Then, you are kinda forced to deal with the "too hot on corner entry" and its a bit frustrating.
 
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