Driver styles/preferences

[timbo]

In fact, for this turn to take place under your conditions, your car must be pointed exactly at the exit straight wall (perpendicular to the straights) when you accelerate, or you've either braked heading out of the corner or accelerated going into the corner. Both of which are bad.

Not sure where you get that.

[Adrian Newby]

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[Jersey Tom]

Inline acceleration will be in the direction of your path. The path is what it is though, defined by your lateral acceleration demand as you go around. If at any point on that path you have spare longitudinal capacity you might as well be using it. In this case of early cornering / late "apex" (clipping), you should start to get that longitudinal ability before the geometric half way point of the corner.

Or as a corollary, if at any point you have spare longitudinal traction, then you must already have enough lateral ability in your tires to stay on that path and not have to worry about going off track.

Of course you can't just mash the throttle immediately or you will overslip the tires and go for a spin (rears will not be able to maintain the path), but otherwise any non-zero throttle application is going to be an improvement for lap time.

[Adrian Newby]

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[Jersey Tom]

No constant radius - to use all available traction you must be constantly braking or accelerating during the entire turn.

True. This is the intent.

you will either be braking while exiting the turn/unwinding, accelerating while entering the turn/winding

Untrue. Just follow the edge of the friction ellipse. Starts at pure braking, then increasing turn / winding while releasing (but still on) brakes, then max cornering, then unwinding while starting to accelerate.

[Adrian Newby]

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[timbo]

If you don't transition from braking to accelerating when you are exactly perpendicular to the two straights (which is bad enough in its own right), you will either be braking while exiting the turn/unwinding, accelerating while entering the turn/winding, or, preferably, if left with those two options, just not using all the available traction. Which is bad, just not as bad.

You would transition from braking to accelerating at the point of maximum curvature of your trajectory. This one's obvious and I don't see your point.

[Jersey Tom]

AN - I don't agree with that, or follow why you see that would be the case. Makes no sense to me. My sentiments are the same as timbo's.

Seems we've agreed that you want to clip late. Slow in, fast out. To achieve that geometrically requires that your point of tightest path radius be before the geometric halfway point of the corner. I see that as unavoidable.

As you approach that point on corner entry, you are on the brakes one way or another. First, braking at max capacity in a straight line and then gradually releasing as your lateral/steering demand increases. At the tightest path point you should be using the tires solely for cornering, and as a result must then be completely off the brakes.

For everything past that point the path radius is increasing, and as a result you are unwinding the steering. As a result of demanding less and less lateral from the tires, you now have the ability to accelerate. If you don't start to accelerate as early as possible (which in this case would be before the 90 degree point of your 180 deg corner), you are not using the most your tires can give you and as a result you are leaving lap time on the table.

As a result, you already should have been gradually increasing throttle before that 90 degree point, so that you can get to wide open as early as possible in the latter half of the corner. At that point with your radius getting bigger you have more than enough lateral capacity to finish the corner - I'm not seeing the circumstance that would require braking while unwinding steering.

[Adrian Newby]

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[Adrian Newby]

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[timbo]

You would transition from braking to accelerating at the point of maximum curvature of your trajectory.

Correct. And what happens if you transition one foot before that? One foot after that? (You had better have SV driving to be that precise! )

You loose some time. But you always gonna loose some time. Or you might actually gain some time if you're lucky.
What's your point? It's a drivers job to be precise.

And which direction are you facing relative to the 180 degree turn?

Tough question to answer. All depends on slip angles.

[timbo]

At the tightest path point you should be using the tires solely for cornering, and as a result must then be completely off the brakes.

Then, as I said previously, you are either not maximizing your available traction, or you are driving a constant radius at that time.

Actually, when you are off the brakes and have not applied the throttle you are not on constant radius. You need some throttle to drive at constant radius.

And even if you get "maximizing your traction/no constant radius" dead-on right, you are still, by definition, accelerating directly at the wall you are trying to avoid.

On the late apex line you should rotate more, and BTW it is NOT directly "by definition". By definition you combine lateral and longitudinal acceleration. How much, when/where IS a driver's style.

[Jersey Tom]

Then, as I said previously, you are either not maximizing your available traction, or you are driving a constant radius at that time.

Define "constant." For a fraction of a second? Sure maybe you could call that "constant" radius cornering - no driver is a robot or using 100% of the car's capability 100% of the time. If you'd like I can post a graphic of Schumacher and Barrichello's throttle and brake usage through the Montreal hairpin - a nice 180 degree turn. Michael has about ~5m of "constant radius," Rubens ~10m. A perfect driver would be 0m. In general though it's a very obviously trail-braked corner. The data is from the traction control days so they both just go flat out on exit and the computer takes care of feathering engine torque appropriately.

[Adrian Newby]

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[Jersey Tom]

Let's take a step back. What point or conclusion or argument are you trying to make at this point? Seems this has become grasping at straws and random talking points.