[upncummr]

This thread is being started in an effort to collect and then disseminate useful knowledge about lapping a road course, generally during an HPDE.

Items of interest are:

1. How to "read" and evaluate the road course. Which corners are most important and which are least important? How to find camber and traction in dry and wet conditions.

2. How to develop a strategy for minimizing lap times and then how to stick to that strategy. How to determine if you're actually sticking to that strategy.

3. How to determine effective tire pressures and temperatures. How do those variables change during the day? How does that track configuration enter into the determination of starting tire pressures?

4. How to increase grip for braking and cornering through management of tire pressures.

If you have something to add to 1 through 4 above based upon your experience or training, please do so. If you'd like to add something beyond 1 through 4, please give it a topic number and I'll add it to the original post (e.g. 5. How to select brake compounds based on track characteristics?).

Thanks!

Gary

[Mushashi]

Well Gary you sure got some good questions. Alright dont quote me on this, as I'm still trying to reinvent my wheel. So you can make fun of me but just dont hurt my feelings. LOL

First you can take a parad lap and than close your eyes and physically simulate going thru the course the correct way.

As for tire pressure, you're gonna have to play it by ear when your at the track, but going into it knowing from the manufacture whats recommended because the varity of tracks and constant surface and tire wear will be a big factor, so I dont have a straight answer there, but start with higher pressure and reduce by every 5lb and once you find the sweet spot +/- by 2lbs.

As for which corner is the most important....its the one leading to the straight. So if you have several connecting corners, the last one is your money corner. It sometimes helps to run it backwards mentally. Priorities should be 1. exit, 2. entry and 3. mid. Alot of people I have worked with seem to think they have to always hit the apex in each corner; complete not true, not required, its just a reference point for the driver, so often I find people trying to hit the same marks and because of this they think they are somehow being consistant. Yeah, consistantly slow. LOL

So what do you think is the idle line for any course? In my book its the line that allows for maximum traction on all four. What is maximum traction? A line that allows for smooth balanced transition. So what is the difference between the idle line and Time attack line? Thats where you will have to find after maximizing your traction and than start to shorten the line till you start to scrub off speed and increase time.

How do you know when you're actually going fast? Are you a G junky?

Here's a little secret-I often ask my fellow students after a few corners: "did you feel that?" They often respond yeah, it felt fast, I felt the car pulling thru the corner. Wrong answer. Its a trick question. The only factors that will indicate improvement is MPH and the clock. So the answer should be I felt nothing-in that you want the car to be as flat on all four as possible with as little G load as possible. What you'll notice is an increase in speed by mph with the same amount of throttle or you'll find more traction which allows for more throttle.

So all in all these are just idea, they may or may not work for you or anyone, just keep in mind there are many other key factors that will effect your results. Its important to have fun and stay safe, you get too serious and involved with improving your time and you'll start to suck.

You can read more about this in "Speed Secrets" my friend! I see that your in MAM neighborhood, the +/- radius corners are great for these ideas, there you'll find the shorter line is not nessarily the quickest way around.


Enjoy,

Cheech

[theGraySTiG]

it's a shame more people haven't added to such a great thread idea. cheech made some excellent points, and i'll re-hash a couple to bump this thread and see if anyone else has input.

first of all, if you want more car control, go slower. put your ego aside, and try to learn a decent line through the track, finding approximately where the apexes are. then you can start adding speed to go as fast as possible out of each turn.

i wholly agree that the most important corner for fast lap times will be the one leading onto the straight. you can be slow and eff up the first couple corners in a sequence, but if you hit the last one onto the straight with the best exit speed, you'll be faster than the person who tackles the earlier corners better, but comes into the last corner too fast.

"1. exit, 2. entry, 3. mid" is also excellent advice for learning specific corners and getting the best lap times.

one thing i have been trying to practice since my first track day last year is how far to turn the steering wheel. it is very easy (at least for me) to turn the wheel too far when trying to exit a turn under acceleration. and what i have found is that most of the time when i am still squealing my tires while coming out of the turn, i just need to unwind the steering wheel a little bit to get more front traction, which actually helps me turn more. of course, if this is not enough, my apex was probably too early.

so for strategy, i would say you need to:
a. determine which corners are the most important--the last one in each set of turns, with the ones that lead onto longer straights being more important.
b. focus on your exit speed out of each complex first. this will remain the most important part of each turn sequence, and should be the major factor in determining the best line.
c. then it depends if you are hot lapping or just trying to be consistently fast. if you want to be consistently fast, you need to develop a good rhythm through the turn complexes, focusing mostly on momentum carried through, but still maintaining the maximum exit speed. if you are hot-lapping, you will probably want to focus on the entry speed into each complex, and then trying to maintain as much momentum as possible through the complex. someone with more experience in time attack might correct me, though.

i have found that most of the time i start to get slower it is because i start trying to come into corners with too much speed. this causes me to scrub too much speed while trying to get my car turned, often never making it to the inside apex of the turn, thus not using all the track, thus not being able to come out of the corner as fast as i did with lower entry speed.

[Mushashi]

Spaghetti Junction drivers are far and few when compared to the 1320 enthusiast. It’s interesting you would bring this thread back to life. It’s been a while since I have logged in and have since gotten out of Subaru's and moved onto new ventures. So I'll happily contribute something else for you to ponder on as it would appear this is something we both have in common.

Few people talk much about mid corner, but its role is just as important as exit and entry. If you think about it there are few who are able to master the mid corner and its examples like Michael Schumacher who proves time after time how they are able to go purple in each sector.

Common sense: You can scrub off speed faster than you can build it. What does that mean? It means you want to bring as much speed with you into the entry as you possibly can with out it impacting your exit. How? By trail braking and slowly turning in one degree at a time and coming off the brakes as quickly as you can start to rotate the car.

Mid corner: Drivers often get the misconception they have to hit each reference point. Entry-Braking, apex-turn in and exit-track out. So they approach each corner the same way, often the same speeds and manner. This is great if you’re a beginner, but if you ever want to start getting faster you might want to try a different approach.

Try this, come into a turn with as much speed as you comfortably can, use turn in reference point and not braking points. The difference is you want to know when you need to get most of your braking done and not when you should start braking. So knowing when you need to start turning will allow you to do this. There is no law that says you have to hit the apex with your tires. What you should be more concerned about is with the added speed can you maintain it and how quickly can you straighten out of the exit so you can start putting the power down as quickly and as much as you possibly can.

You see a lot of driver sacrifice their entry speed for their exit, so they come in at the same speed everything, start braking at the same spot and turn in the same way and track out the same way. Only use as much as what the car is telling you, you don’t need to exaggerate unnecessary movement or occupy space that is not going to benefit you.


Here is another approach I often use you may find interesting. This is what I do when I’m getting familiar with a new car or a track. The first few sessions I’ll start by turning in early at a comfortable speed, taking the tighter line, staying on the inside as long as possible and I start to apply power as quickly as I can while trying to keep the car on that line.

Next session I work on finding all my turn in points, you’ll want the ones that will yield the fastest exit speeds. So basically sometimes the less steering the better, less hang time in the corner the better, all depending on the type or corner.

And the last piece, a session after being satisfied with the first two. I will start taking a wide line, I’ll run the outside of the course and stay out there as much as possible, using up as much of the track as I can. The intent of these three exercises when combined will hopefully result in providing you a good understand of the characteristics of how your car will react. This will quickly help you start to sort things our and define the fastest way around the course.

Remember to approach each exercise slowly and than start to apply power progressively and smoothly. How you apply your inputs will determine your results. And always look for run offs during practice sessions.

Another day another mile stone!

Enjoy,

-Cheech

[theGraySTiG]

very cool. i like your approach, and will have to try that during my last few track days this year. believe it or not, i really do try to focus on the turn-in point more than the braking point...but most of the time, i am more focused on the apex than the turn-in point when i get near the corner. this helps me visualize how fast I should be approaching to be able to get the car rotated through the turn, but i sometimes end up cheating in a bit early, which i am trying to correct. i do sacrifice entry speed for exit speed, but that's b/c i'm not doing time attack, and i want to make sure i make the turn on the tarmac first and foremost. however in later sessions, i start coming in faster and faster, usually until i am sacrificing exit speed by coming in too fast.

my main focus for each day has been maintaining smoothness, but i am still very new to this as i have only done 5 track days so far...i didn't start until i got my STi last August.

on a side note, i've found that there are quite a few STi's at every track day I attend, and many are on here. however, a few have said they don't want people to think they are tracking their car in case they decide to sell it later. funny thing is i'd rather buy a car from any of them before any of the strip frequenters or street racers. and i would never buy an older car from a garage queen...but that's neither here nor there.

thanks for the pointers, cheech. it will give me a focused plan that i like the sound of for my next event. it is a track i have driven a couple of times now, and i really wasn't sure what to work on last time i was on it...i knew there was more speed to be found, but i was just focusing on smoothness, and not finding much. thanks again!

[Track]

What a great topic!

I am a little surprised that no one has mentioned the following 2 things which have really helped me:

1) Walking the track with a seasoned driver. Having someone who knows the track well pointing out braking, turn-in, apex, and exit points has been incredible. Jim Hall kart school used to combine walking/talking with an instructor while another instructor would circulate the track at 80%, 90% and 100% at a few major corners. As the speed/intensity went up, it was awesome to see the kart going at it's limit with a skilled pilot at the helm.
2) Low speed lead/follow behind a seasoned driver. The "line" isn't always where my beginner's eager yet stupid brain says it is. I had to revise my initial expected lines after a couple of laps behind a pro driver who was gracious enough to help me. I was blown away the difference this made. After knowing the fast way through a course, I could then begin incrementally "push" more as I grew more comfortable. This is especially meaningful in a car as opposed to a kart.

Oh yeah and the biggest one for me is, "Slow in, fast out".

Let's keep this topic going!

[theGraySTiG]

i've never been to a track where you were allowed to walk it first. plus, on a 2.5-mile road course, i'd think that could take quite a while. most kart tracks are shorter, but not necessarily.

following a seasoned driver is something i have been doing since i started working with timing and scoring. "my instructor" works with me there, and when we get a chance to head out onto the track, i try to follow him if i have never been there. this is very helpful for my first few laps. however, i seem to have a problem really learning the line well this way. unless i am kind of far off line, this doesn't seem to affect my driving much b/c i am trying not to focus on the car in front of me too much...when i do, i tend to drive worse. i may very well be doing several things wrong to cause this problem, but i can't seem to figure out how to follow someone very closely while trying to hold their exact line...or maybe i just need more practice.