Racing line between alternate direction corners

[beelsebob]

I'll use Tim Wright's terminology.

Can I define a case 1.5 situation? This is two grip-limited opposite-direction corners separated by significant longitudinal accel/braking, but the accel itself is still grip limited, not power limited. In other words not a left-right transient where the velocity is roughly constant through the whole process.

An F1 car can always generate higher G-forces in braking than acceleration. What does this imply for the ideal line for case 1.5? I think this means the ideal entry/exit width will not be an even tradeoff. There will be some asymmetry for ideal exit width vs ideal entry width. I'm not sure which way is optimum-- wide exit and tight entry, or the other way around?

I think in F1, if you have an acceleration zone between the two corners, you're always going to take wide entry and exit and diagonal the straight (barring any other hazard)... You have to get the two corners really close (e.g. fanges at Spa) before they start taking a wide entry, but a tight exit, and then a tight entry and wide exit to the second corner.

[bill shoe]

I think the ideal race track would be as wide as possible. As you reduce the track constraints you increase the variation and challenge. Ideally it would be a continuous sheet of pavement with the corner apexes marked (by cones or something) and nothing else. There would be a vast array of lines possible through every corner ranging from haripin tight to really wide and sweeping.

It would look kind of like a giant autocross, but with fewer cones than a typical autocross. Make it the size of a 4-mile racetrack and it gets interesting. This is the kind of thing that should have been done with the $1 billion spent on Abu Dhabi.

As a bonus, this approach would reduce Herman Tilke to a minimum-wage cone setter.

[timbo]

Yes but let's take the Ascari exit. For most cars it's easily flat out anyways; so it's not grip limited for one thing.

But what if you'd actually have to lift to take a tighter line?
There's very fine balance between power/grip limited.

[raymondu999]

I get what you're getting at timbo; but I don't think Ascari exit is a good example. I am absolutely convinced that that corner can and will be flat even then

[Belatti]

Sorry to interrupt the F1 based discussion. I use to work with low power openwheelers in open and windy tracks. A compass and an anomometer (and a driver with will to listen) worths instantly 0.1 secs a lap using the correct trajectories in straights. Sometimes that involves making weird moves and sometimes you have to correct those trajectories during the day. I suggest you people to speak with someone who masters the art of sailing about this

[Tim.Wright]

Thats a good point. In my experience (mainly simulation based) I can tell you that the trajectory is probably THE most important part of a driving style, and where most of the speed lies when learning a new track. Though its rarley talked about because the drivers converge very quickly to a common optimum.

This is why, even in a car a finely tuned as an F1 car, the drivers still throw them over the curbs at Monza. It is simply faster to do that then try to tune the car to go around the corner.

And of course, the situation is exaggerated in low powered cars like formula ford.

Tim