Driver styles/preferences

[Jersey Tom]

If you feed power on that early, then fight the increased lateral acceleration all the way around, it ends up taking you longer to go to full throttle, and you will be closer to the outside wall when you do it.

There's no "fighting" it though. The moment the steering starts to unwind, you're release tire lateral demand - you have extra grip to spare. The longitudinal acceleration is free. This is the whole premise of "late apexing" and why it works for getting exit speed - start to unwind the steering as early as possible to free up the tires to accelerate through the rest of the corner and down the ensuing straight.

In any event, I still see no feasible way to brake or accelerate on a constant radius path without giving up a lot of mid corner speed by not using the full capacity of the tires. To me it's physically impossible. Either you brake and accelerate on a constant radius corner trajectory and are slow mid-corner, or you have a fast mid corner speed with no ability to brake or accelerate while cornering - and it all has to be done only in a straight line.

[Adrian Newby]

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[Adrian Newby]

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[Jersey Tom]

Ok, so what's the talk of trail braking on constant radius then?

[Adrian Newby]

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[Jersey Tom]

Oh it's possible, it's just invariably slow (or not ideal). Again, it's not just my opinion on it, I'd say it's fairly well proven out. Watching an onboard it's pretty clear to see steering being gradually added on entry as the brakes are being released. The only time the steering or trajectory winds up being constant is when the driver is off the brakes and neutral throttle (tends to be momentary).

[Adrian Newby]

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[raymondu999]

I sort of get Newby's concern. If you were to do a sort of free body diagram and break down that drive torque into vector components - then obviously the most "efficient" acceleration on power would need to be applied in the vector direction that is parallel to the exit straight. Your concern is the vector component of that on-power acceleration that is sent perpendicular to the exit straight - or tangential to the apex - is basically "useless" because it's not getting you any closer towards finishing the next straight, correct?

[Jersey Tom]

I'm just stating that across the board, the method pretty well universally used by professional drivers is to take a tightening radius on corner entry - up until the point they're off the brakes. At the very least, I have never seen anyone do differently. It is the method coached in driving schools.

It is of course possible that everyone has it all wrong. Or, it is possible that it is the fastest way to set up a corner.

Regarding on-throttle acceleration, that vector is in the direction of the cars trajectory. Yes, through a corner it is never pointed exactly parallel to the next straightaway until you're out of the corner. However, taking the "late apex" approach and putting your "apogee" before the geometric halfway point in a corner, you get the car pointed before you've hit the halfway point.

The below graphic (not mine) shows a 90 degree corner. The halfway point is 45 degrees. By that halfway point however, the car is already turned more than 45 degrees. The "apogee" as it were (point of tightest path radius) is somewhere between "turn in" and "late apex" and is the point at which the driver should start to apply throttle.


Or in the 180 degree example (for which I do not have a graphic), your car trajectory would be "perpendicular to the straightaways" before the geometric 90 degree point of the road. This is why you can get on throttle before half way - the car is already pointed, and the only way to accomplish this is by putting your tightest radius point early.

[Adrian Newby]

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[raymondu999]

Ok, you must be right then. I'm not trying to convince anyone.

The last I will say on it is that the physics of it that you do know, you are correct on (but for the wrong reasons). And that the physics of it you don't know... you don't know because of the physics you do know.

But more than anything, you are just looking at it wrong.

Wow. Mate, take a deep breath, and just re-read some of the things JT is saying. There's a reason why he's in the Top 5 highest voted posters on the board. JT is a respected member of the boards, and I myself have certainly learnt a great deal from his posts.

If my previous post was indeed highlighting the correct concern on your part, here's my take on it. As a race driver, your job on the straight is to get the best possible acceleration (aka full throttle) towards the end of the straight. There is no question there. Once you get to the phase where your accelerative torque is used 100% longitudinally to the next corner, everyone is flat out - and as such, no advantage can be gained there, because obviously, if you're already at full throttle, you can't accelerate quicker.

Obviously different lines will demand different levels of lat/long grip at different phases of the corner. But at some point on the straight, there is a point where EVERYBODY, regardless of the line they took through the preceding corner, reaches "100% longitudinal, 0% lateral" - am I right?

Let's call that point "Point X." Are we agreed so far?

As such, your job in the corner is not to get maximum ponies pointed down the next straight. Your job, in and around the corner, is to hit Point X with as much speed as possible, not to begin Point X earlier.

[Adrian Newby]

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[raymondu999]

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[Adrian Newby]

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[raymondu999]

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