Veloce Raptor

+1 to what Cory said about the consequences of not looking far enough ahead as well as most folks not feeling the effects of nuanced set up changes. By the. Way, Cory, I am at Road Atlanta and the guy who bought your M3 is here

guardsredcab

Dave, it's Cory's car that Howard bought? Are you coaching him? He's being sneaky about this!

Veloce Raptor

Yes, it's Howard's car. I am coaching all of his run group as well as SuperSolo for PBOC

coryf

That is awesome! The M3 was my daily driver for 3 years. I would autox it with the recaro baby seat in the back. It's amazing how small a world it is. Hopefully he is having fun with it and not beating it up too bad. Really enjoyed that car. Replaced it with a little older e39 m5.

Veloce Raptor

Yes indeed the world is small! He is doing well and enjoying the heck out of the car! Without the baby seat

tahoelife

First off I have just finished reading this entire post some of it multiple times thanks so much to all who have contributed ! So my background is and has been coaching/teaching sports like very high level downhill skiing into motocross and other alternative sports like snowmobiling and surfing. I firmly believe my background in those sports has given me a good platform for learning to drive my car well and the importance of having instruction and coaching.. My friend who got me started in doing DE s and TT runs recently went through a instructor evaluation through PCA and something I hope to in the future. One question I have that has been somewhat addressed here is a training program for instructors. I understand that organizations like PCA are volunteer but in every other platform I have been involved with there was a program for teaching the "teachers" how to teach. When my friend applied to become an instructor he and I both thought they would do just that teach him how to teach which was not the case. They just evaluated his abilities not just to drive his car but through role playing just "tested" him. I understand getting checked off to teach but do not understand why if there seems to be such a shortage of instructors why there is not a "under study" program. In ski teaching there is a huge process to be able to teach higher levels and a way to become a teacher of the teachers and then on to become the examiner. I know this post is way to long and rambling on so I apologize and do greatly appreciate all the knowledge provided here just curious as to why there is not a platform to teach someone who wants to pursue that someday?

BBMGT3

Hi coaches

My subject for today is Power-Oversteer, controlling the rear of the car while under power.

I have a natural fear of the following scenario:
- Power at apex
- Reach exit or on the way to exit curb
- Back steps out
(Fear scenario) I try to correct, but in the process of doing so the car goes into the wall. The closer to the exit curb I am, the more wary I am and I tend to time my throttle application so that I am "safe".

Counter-intuitively, if the rear breaks loose on turn in / trail braking have no issue. Like, none at all.

Thought I've watched tons of videos of top drivers kicking the back out, correcting, keeping the car on or near the line, staying flat or nearly flat, and continuing to turn, I don't understand the physics of it.

So, any tips or advice on how to work on this?

Adam@Autometrics

I would recommend some time on the skidpad (wet initially, then dry). If you can get comfortable "catching" the car on the skidpad where there's no chance to hit any wall, then that confidence will eventually transfer to the race track. This certainly comes more natural to some drivers than others, but it can be learned, and the skidpad is the most effective and safe way I know to do that.

BBMGT3

Thanks Adam!

I tried a wet skidpad. The sensation was very odd - initial understeer at low power but then snap oversteer when you overdo it. But I could catch it without issue. But there are no curbs or walls and the sensation is totally different - plus I don't have a reference to how far the car is moving while I am on opposite lock.

ProCoach

This sounds less like a "power oversteer" issue than a crisis-management scenario. Let's dissect your issues a little, first.

If you have no trouble when "the rear breaks loose on turn in/trail braking, have no issue" (my bold emphasis added), then that's good and your "butt gyro" may be reasonably well calibrated. That's a good thing.

I think the real focus should be your phenomena described as "the closer to the exit curb I am, the more wary I am and I tend to time my throttle application so that I am "safe"."

Your statement in bold is, in my opinion, the root-cause of your fear and a substantial ingredient that could more easily cause the scenario you most fear.

A better understanding of the physics will help you understand why top drivers (or drivers that do understand and use those physics) are able to achieve what you're observing.

When you recover or stop the rear of the car stepping out under turn in/trail braking, you are reacting to perhaps a more abrupt weight distribution shift that causes that instability. When a driver "kicks the back end out, corrects, keeping the car on or near the line and continuing to turn," they are being pro-active and at their discretion, breaking traction at both the front (the correction that continues through the rear end breakaway) and at the rear (kicking the rear out), more perfectly aiming the car downstream and avoiding the exit curbing until most of the lateral loading has ebbed.

This last underlined state will fix your issue and ameliorate your fear. A car steps out at exit by touching the exit curb when the front tires are loaded disproportionately due to a) running wide of the inside apex curb, b) being off-throttle or off-throttle enough to weight the front tires such that the car pivots on the resistance met when that tire hits the outside curb (can you tell I've done that a few times? )

Your delay in throttle commitment to the exit seals your fate, if you are unfortunate to hit that curb off-throttle or late on the throttle. It's a timing issue.

First order of business, make darn sure you hit EVERY inside curb. Six inches in a the apex equals a foot in at track-out, unless you're very, very early!

Second order of business, pick a slow, longer corner that you're comfortable letting the rear come out under turn in/trail braking and SUSTAIN that kick out for longer through the corner, balancing that "slip angle" with the throttle. THAT'S what you're seeing on the videos you cite.

Then, jack it up as you gain experience and confidence.

To prevent your nightmare from taking place, AS SOON AS IT BECOMES CLEAR that you may run out of room and hit the track out curb at ANY greater angle than parallel or near parallel, open the wheel and go as straight as you can. This will prevent the spin to the inside at the exit. Sear this automatic response in your head and you'll have no trouble. Good luck!

Veloce Raptor

+2.

To add to what Adam and Peter have said, I will also offer this: many top level drivers, when at or near the limit, will correct for the sort of oversteer you describe very subtly. Meaning that, in addition to the obvious small (or sopmetimes large LOL) steering corrections, they are making tiny modulations of the throttle to help reestablish more rear tire griip. A wet skidpad, with mor epractice, is a perfect place to develop the skill of tiny throttle modulations, which can have surprisingly large impacts on the griip & attitude of the car when the rear loses grip.

pontifex4

Peter, this is exactly what I need to learn to do, as well, and I take your point that hitting the apex correctly leaves you the most room at track out, but can you explain the dynamics of the sentence that I've bolded below a little more?

BBMGT3

Thanks Lolaman (Peter?) and Dave,

So there are two instances where power-oversteer is a problem, one more severe than the other

The first being at the apex, if you come on too hard and the back steps out. This is relatively easy to deal with, because you have time to sort it out. But sorting it out without losing a lot of time is another story.

The second is being WOT with steering angle / lateral load still applied and hitting the exit curb with the outside (loaded) wheels. To say you hit the nail on the head that the fear of this scenario is holding me back is putting it mildly. I have an expectation that the rear breaking away will be far more abrupt than during turn in / trail braking, even though I'm not sure that is actually the case. I think the crux of it is that on turn in I know the car is still slowing down, so I "believe" that in the course of the correction the car slows and re-grips. No crisis to manage. Under power, the car is accelerating, so I don't see how you can go from losing grip @ X speed to getting it back at X++ speed. Maybe I'm over complicating it!

I will try to sustain a drift through a long corner with no walls nearby! Good-bye tires... lol

Veloce Raptor

DING DING! You have just self-analyzed the crux of the issue right here.

This tells me that you are not doing enough rotation early enough in the corner, and thus instead of unwinding steering as you apply power on th eway to WOT, you are holding (or even adding) steering. This will never end well IMO. You need to focus on starting the rotation sooner and getting more of it done before you even get to the apex. This will enable you to begin unwinding steering at 9or even slightly before) apex, which will give you a MUCH more stable race car, enable WOT sooner, nearly eliminate any Code Brown moments of lurid power oversteer, and make you overall faster and more relaxed in the car.

KaiB

You need to focus on starting the rotation sooner

This single point is huge...