Be Nice! A Stupid Question For Oppo From An Idiot

"Lets Just Drive" (lets-just-drive)
04/07/2014 at 23:12 • Filed to: None

Hey Oppo,

This is going to sound fucktarded. I know that because it sounds fucktarded in my head, but I dunno the answer. So, the question is this:

Does the apex of a corner change from one vehicle to another, or just how it's approached?

I ask because I was just watching a bunch of different cars driven by different drivers (probably of different skill levels) going around the same corner and the variety of ways through was pretty wide with more than one looking like the fast line. I've never spent time on a track and I'm not a huge motorsport fan so my knowledge is pretty crap.

Even in watching a variety of cars taken around the TG track, depending on the car (FWD, AWD, RWD... Heavy, Light, FR, MR, RR yadda yadday) the approach seems slightly different car to car. I'm guessing the apex never moves, you just adjust as a driver depending on what you're driving.

But hopefully someone can enlighten me. Dusty? Anyone?

DISCUSSION (44)

AthomSfere > Lets Just Drive
04/07/2014 at 23:14

The racing apex is not the geometrical apex. So yes, it varies from car to car, setup to setup, and somewhat lap to lap.

It's a "Porch-uh" > Lets Just Drive
04/07/2014 at 23:14

The apex is a fixed point. Drivers take different lines depending on their car, style, track conditions, etc.

Ike > Lets Just Drive
04/07/2014 at 23:16

apex Is the point on which you travel the shortest distance though a turn, it doesn't change vehicle to vehicle, what can change is the fastest method of getting thought the corner; based on the type of vehicle and drive line. How you make contact with the apex, that depends on the car, the apex is constant

Bad Idea Hat > Lets Just Drive
04/07/2014 at 23:16

This is going to be a quasi-metaphysical discussion. Can't wait to see the answers.

The Transporter > Lets Just Drive
04/07/2014 at 23:17

Yes. Depending on the handling of the car, you might need to chose a different line when tackling the same corner with different cars.

Arch Duke Maxyenko, Shit Talk Extraordinaire > Lets Just Drive
04/07/2014 at 23:17

Yes, it is a constantly changing 4 dimensional entity.

Source.

pfftballer > Lets Just Drive
04/07/2014 at 23:18

A turn has only one apex. Where the turn you are making with your car apexes relative to the actual apex on the track is what people mean by early or late apex. In a traditional turn a late apex is preferable/faster because it lets you get back on the throttle faster. Apex too early, before you are through the turn and you will run off the track wide. Hope that helps.

BlazinAce - Doctor of Internal Combustion > AthomSfere
04/07/2014 at 23:18

Well put. I think it may even vary from driver to driver, depending on their individual styles, with the same car, specially in successive corners where they'd be able to choose to lose a little on one to make up on the entry or exit of the next one.

Lets Just Drive > AthomSfere
04/07/2014 at 23:19

Feeling less of a fuckwit now. Thanks.

Lets Just Drive > Ike
04/07/2014 at 23:19

My assumption didn't make an ass out of me. That's a rewarding sensation.

Lets Just Drive > It's a "Porch-uh"
04/07/2014 at 23:20

The apex never moves, but the relative approach changes depending on various factors such as speed, power, grip etc etc. Yes?

Lets Just Drive > The Transporter
04/07/2014 at 23:20

But the apex remains a constant, it's simply the line through the apex which changes?

Lets Just Drive > Arch Duke Maxyenko, Shit Talk Extraordinaire
04/07/2014 at 23:21

At first, I thought you were being a dick. Hah.

Thanks.

Lets Just Drive > Bad Idea Hat
04/07/2014 at 23:21

Because it's being held on Oppo, though, it should at least be civil and informative.

BJ > Lets Just Drive
04/07/2014 at 23:21

According to Wikipedia: "The apex or clipping point is often used in motorsport , though other racing sports such as skiing and bicycling have similar concepts of an ideal line. The apex is often but not always, the geometric center of the turn. Hitting the apex allows the vehicle to take the straightest line and maintain the highest speed through that specific corner . It is also the tightest part of a corner."

http://en.wikipedia.org/wiki/Apex_%28r…

So, maybe?

It's the tightest part of the corner, and therefore can't change from a geometry standpoint.

However, the racing line, and where you clip the corner depending on that line, changes from car to car. This is your car's "apex" because it allows you to carry the maximum amount of speed through a corner.

AthomSfere > Bad Idea Hat
04/07/2014 at 23:21

You don't hit the apex, as much as you feel it. And it feels you. When you have nailed the apex, you are one with the racing line of the ancestral inertia gods, and you accelerate out of the turn reincarnated as a more complete driver; mentally, physically, you are better now than you were before the apex. It is not a moment in time, but an ever changing and evolving relationship with the car...

AthomSfere > BlazinAce - Doctor of Internal Combustion
04/07/2014 at 23:23

I'd buy that, for sure. Especially where one driver might risk a less ideal turn on one for a pass where maybe another would rather try to maintain an ideal line for the next turn or two for example.

Lets Just Drive > pfftballer
04/07/2014 at 23:24

Mind blown.

A corner has an apex, a physical point at which the corner transitions but there is also a relative apex which depends on various factors. The apex exists as a fixed point but the action of approaching and passing through the apex is affected by various factors resulting in the terms early or late apex to describe the motion.

I get it, I think. There are two elements to consider; a fixed point and the transition through that fixed point. Da?

The Transporter > Lets Just Drive
04/07/2014 at 23:26

Not necessarily. Decreasing radius turns lend themselves to a plethora of different potential apexes depending on the handling of the car. Turn 17 at Sebring is like this.

JGrabowMSt > Lets Just Drive
04/07/2014 at 23:26

The apex of a corner is always the apex of the corner. It's a specific point.

The racing line is the way to get around the track in the quickest possible time.

Driver ability and vehicle is what causes the change. If I tend to brake earlier going into the turn, I'll have a different line compared to someone who brakes later. If the car is more powerful, it will be able to brake later and turn differently compared to a less powerful car that has to keep the momentum going.

So in short, the apex doesn't change, and the racing line doesn't change because they are defined and specific. You're just seeing the difference in the driver+cars ability to travel along that line.

Lets Just Drive > BJ
04/07/2014 at 23:26

Others have educated me.

The apex is a fixed point, but how one transitions along that apex depends on various factors and results in what people describe as a late or early apex - easily affected by the type and description of vehicle one is driving.

The apex always remains fixed, but the fastest way to "apex" a corner changes depending on the aforementioned various factors.

Racing are smarterer then I thinked.

Bad Idea Hat > Lets Just Drive
04/07/2014 at 23:26

Oh yeah, I wasn't being sarcastic. I can see widely varied answers incoming.

Lets Just Drive > The Transporter
04/07/2014 at 23:28

Which brings up another interesting question; can a corner have multiple apexes such as you describe in decreasing or increasing radius turns?

I'm realizing right now that all my years of fakery on PC and console have taught me naught and that the only way I'm ever going to really learn, outside of more research (abstract though it be), is to get my ass on a track and have a go.

beardsbynelly - Rikerbeard > Lets Just Drive
04/07/2014 at 23:31

every corner has a fixed apex. it doesn't change for the corner but it may change for each car.

Early or Late apex determines what period the apex comes from, for example, You may have a Mesozaic Apex for a chicane and be chased by a Prestosuchus or a late apex for a hairpin in a 911 and have to deal with a Tasmanian Devil gnawing at your gonads.

Lets Just Drive > JGrabowMSt
04/07/2014 at 23:31

I should have just waited for your reply.

Also, I'm checking up on that last package. Hopefully an answer soon because, yes, the Subie arrived.

I was just watching Randy Pobst take a bunch of different cars around Leguna Seca, after making this post, and I see what you're saying now. Regardless of the car, he followed the same line around the whole track and clipped apexes at exactly the same point. He even describes the tendency of one car to want to take the corner differently than another.

I'm getting it, methinks.

Lets Just Drive > beardsbynelly - Rikerbeard
04/07/2014 at 23:32

Excellent reply.

Chuck 2(O=[][]=O)2 > Lets Just Drive
04/07/2014 at 23:36

Just watch vintage British racing with the Minis and Ford Falcons. Two very different racing lines.

AthomSfere > Lets Just Drive
04/07/2014 at 23:39

No, the apex in racing is when you want to lay on the gas and begin your exit. It is not a fixed point except for in that particular maneuver.

beardsbynelly - Rikerbeard > Lets Just Drive
04/07/2014 at 23:40

I visited a dinosaur museum on the weekend. I got part of a fossilized starfish for completing a kids question sheet.

AthomSfere > Lets Just Drive
04/07/2014 at 23:41

Except the Apex is not necessarily a fixed point.

Arch Duke Maxyenko, Shit Talk Extraordinaire > Lets Just Drive
04/07/2014 at 23:45

See, time is a cube!

Lets Just Drive > Chuck 2(O=[][]=O)2
04/07/2014 at 23:47

The same FP article from Goodwood is what set me about this train of thought?

The Transporter > Lets Just Drive
04/07/2014 at 23:49

Going back to turn 17 at Sebring, it's actually two corners that are very close to one another. Depending on the handling and setup of the car and the driver skill, you might end up with two apexes. A high downforce car such as the Audi R18 e-tron might just take the entire corner incredibly tight, hugging the inside wall the entire way. An MR car, such as a Porsche, will get squirrely on braking but stabilize on acceleration in a turn, so somebody like Patrick Dempsey might brake in a straight line before corner entry and then gradually increase the throttle as he decreases his turn radius, hitting the apex approximately 135 degrees from corner entry. An FR car, such as a Corvette or Viper is more stable in braking but less so in acceleration through a corner, so somebody like Jan Magnussen might brake later than Dempsey, hitting one apex at 45 degrees from corner entry, going a bit wide, and then slowly laying on power as he clips the second apex at 135 degrees (assuming he even hits the second apex at all) and then applying full power as he exits the corner.

Also, autocross will teach you all the same stuff and is way cheaper than a track day if there's an autocross club near you.

Chuck 2(O=[][]=O)2 > Lets Just Drive
04/07/2014 at 23:49

Yep, you really only realize it when the cars are close together, but completely different.

Lets Just Drive > Arch Duke Maxyenko, Shit Talk Extraordinaire
04/07/2014 at 23:54

That movie was such a mindfuck for it's day.

Arch Duke Maxyenko, Shit Talk Extraordinaire > Lets Just Drive
04/07/2014 at 23:56

Speaking of, have you watched Primer ? Because you should.

Lets Just Drive > The Transporter
04/08/2014 at 00:00

There is, as I discovered last summer and they hold events in the huge, open lot of our Speedway. Our Speedway on the other hand is a bit of a joke and not really worth mention as an option. If you're curious, search "Western Speedway" in Victoria, BC Canada.

I plan on attending this summer and driving the club car rather than my own (they have an autocross prepped Civic which, while front drive, is supposedly an excellent teaching tool. Having been in contact with them and encouraged that my Mustang would be welcome but might mean I leave with a sour taste in my mouth given the set up's they use I've decided to start in their car.

The realization that everything learned from years of simulation doesn't amount to much and the fact that even aggressive driving on roads which aren't racetracks has it's limits in terms of instruction is a hard one. I've been a car guy for much of my life but I've never explored the track side of things due to limited access in my area. That needs to change.

Lets Just Drive > Arch Duke Maxyenko, Shit Talk Extraordinaire
04/08/2014 at 00:01

Yes, but have you watched Pi?

The Transporter > Lets Just Drive
04/08/2014 at 00:34

Sims are a good safe way to learn the basics, but doing it too much trains you to rely on only one or two senses and can build a certain overconfidence. Driving a real car on a track or autocross course uses all five senses at once. Taking a lap at full speed for the first time can be somewhat overwhelming even though you might be moving significantly slower than in a video game. The vibrations are something that even a force feedback wheel can't prepare you for. The sounds are louder and more nuanced than speakers can ever produce. You can smell and sometimes even taste the tires and brake pads when you put them under stress in a corner.

All of these things bombard your brain at once, overwhelming it. It fools you into thinking that you're moving way faster than you actually are. After the first lap or two you're going to think to yourself "I'm not cut out for this shit," but after a few more laps your brain starts to get used to it and starts to drown out the unimportant information. Then you start to get faster. Once your brain starts to make sense of those shaky images entering your eyeballs, you can start to apply all of that stuff you learned about cornering from video games.

Lets Just Drive > The Transporter
04/08/2014 at 00:44

My on-road confidence is always high and never in doubt but I imagine that will all change on a proper track.

You can tell a Finn but you can't tell him much > Lets Just Drive
04/08/2014 at 11:07

Kinja'd!!!

The dark blue is an early apex, the light blue is a late apex and the green is the true apex. In racing you do adjust where you apex depending on car setup, course configuration and a lot of other things. Picture is from the Wikipedia article on racing lines .

Say you're going from a long fast straight into a tight slow section. In that case you would want an early apex (dark blue) since that would allow you to carry your speed from the fast portion of the course longer. If you are going from a slow section to a long straight a late apex (light blue) would be better as that would allow you to get on the gas sooner and build more speed on the fast section.

That is my greatly oversimplified explanation of it. I'm sure you can find some pretty good videos on the YouTube if you dig around. So your question wasn't really dumb at all.

Lets Just Drive > You can tell a Finn but you can't tell him much
04/08/2014 at 14:01

Thanks! This was actually a very, very helpful answer probably likely because you took the time to simply explain a complex idea. Thank you!

It's a "Porch-uh" > Lets Just Drive
04/08/2014 at 14:11

Correct. The apex is the geometric center of the corner, so math determines where it is. While you will often want to hit the apex, it's not always the best thing to do depending on the corner before and after. Sometimes you will want to clip the corner after (late apex), or before (early apex), or completely miss it (hitting the apex would put you too far off the optimum line for the next corner and slow you too much).

It's a "Porch-uh" > The Transporter
04/08/2014 at 14:15

That's a bit confusing, and not exactly true. There's always one apex, the geometric apex. Depending on the optimum racing line, you may apex early, late, or miss it. "Your" apex is not necessarily "the" apex.