http://www.youtube.com/watch?v=eXV9nHhhz4E

Please ignore the excited comments =)

and do critic what u notice on my drive. i know there is many mistakes. and pardon the shaky bad camera mount

 

Ahh... Hallett. Fun track. Biggest thing I noticed that you should work on is heel-toe. It will keep you from upsetting the car when you are downshifting. I saw at least once where the car got squirrely because you didn't heel-toe (or didn't do it properly). You can practice this on the street, too.

Just for comparison, here's a video of me at Hallett:
Video.
I was making about 10hp over stock and using Kumho Victoracers on an otherwise stock suspension at the time. I'm not saying my driving is better or worse (but I know that there are at least two corners that I never felt good about). Just something you can look at for comparison or entertainment value.


BTW... it didn't appear that point-bys were required for passing. I would never want to run with a group that didn't require point-bys for passing in the beginner groups. Just because a novice driver isn't on the racing line doesn't mean that he's intending to let you pass. The only way to be sure of his intentions is for him to signal to you. Otherwise, you could end up with unnecessary car-to-car contact.

 

Running the reservoir down to nearly empty (below the MIN line) won't hurt the seals in the MC at all. In very old cars, in which the brakes have never been bled, the seals can be damaged in bleeding the brakes by being dragged over old and corroded portions of the master cylinder that hasn't been regularly "wiped clean". Shouldn't be a concern on your S2000.

Hankook k106's aren't "all-season" tires, but they don't seem to be very track-oriented either (treadwear rating >300). Anyway, 40psi hot pressure is not unusual. About right for less-than-trackworthy tires, and streetish camber (<2deg).

Driving at the track takes some getting used to. Seat time and some good coaching will improve things a lot.

Regarding your braking timing issues, and the idea of "couldn't get my legs off the brake and back to the throttle before turn in.":
FWIW, I'm the rare instructor that encourages trail-braking early on. Most instructors (mine from way back included) insisted on my braking only in a straight line and then turning in. IMO, this is unnatural and never felt right. You should normally be trailing off the brakes at turn-in, smoothly trading braking effort for steering angle. Abruptly jumping off the brakes BEFORE turn-in just doesn't work well.

IMO, instructors insisting that their student brake ONLY in a straight line at first only delays progress and makes corner entry more clumsy and awkward than it needs to be.

At an autoX once I had to reassure a newB driving her husband's 350Z that she was RIGHT to still be on the brakes at corner entry. She was doing GREAT, but told me she was having trouble getting off the brakes before turn-in! "Don't worry, yer doing fine" sez I...

I'm sure there are dissenting opinions on this forum, but I really think that insisting students be totally OFF the brakes at turn-in is not a good idea!

 

mxt_77: thanks for the great comment , i always find the brake pedal too high compared to my throttle pedal and i have to depressed the brake harder for a smoother blip on the throttle. any more advise on that?

great video you have there mxt

Zdan: i've read some article from skip barber school about braking and turning at the same time upon reaching the apex of the corner ( trail braking to the apex) too but am unsure how to apply the theory correctly especially how to lift off the brakes and back to throttle without upsetting the rear from coming out. any further advise?

 

You have to smoothly heel/toe (left-side-of-foot/right-side-of-foot, really) transfer from brake to throttle. Or you could try left-foot braking! Nah, hold off on that...

Again, the idea is that you are smoothly getting off the brakes as you are smoothly turning into the corner. Trading pressure on the brake pedal for steering angle, you're trading braking g's for cornering g's. Then as you exit you trade off cornering g's for acceleration.

The important thing is to do everything smooove. No abrupt slamming on the brakes, no abrupt lift off the brake pedal, gentle steering inputs, etc. etc.

Get to the track again as soon as you can, seat time works wonders (usually!).

 

thanks for the tip Zdan , i'd appreciate more feedback from veteran drivers on technique to practise on since the instructor didn't comment much on my driving but just merely showing me around the track and certain object to take note for a better line and exit point

 

Different people have different forms. Some use the sides of their foot (inside for brake, outside for throttle). I actually use the ball of my foot & my heel because I have relatively small, narrow feet. This also makes it easier (in my mind) to separate the two movements, since I'm using different muscles to modulate the brake vs throttle. If you have long legs, you may not be able to get the right angle to do a true heel-toe because your knee might hit the steering column, so you may be stuck using the inside/outside of your foot.

As with anything, practice makes perfect. Do it in your daily commute, everytime you decelerate to take a corner. Obviously, you won't have to match at high revs (unless you want everybody staring at you), but just practice the movement of braking with one part of your foot while simultaneously blipping the throttle with another part. I even do it in my FWD Accord on my daily drive.
Left-foot braking is a totally different concept that serves a totally different purpose. It's generally used for keeping a car balanced through a corner, whereas heel-toe is just a mechanism for completing a rev-matched downshift while other things are occurring (in this case, braking). With a manual gearbox, you can't very well downshift while left-foot braking (well... you could, but...).

For the record... I'm by no means an expert. These are just some things that I've picked up during my own learning experiences.

 

so u guys rev-match and heel n toe in your daily commute? * are u able achieve speed to do this?*

i have some questions general on driving a s2k


1.)lifting foot off throttle to slow down , is it alright? ( mid corner)

2.)do all braking and downshifting before turn in? or trail brake and shift while turning in?

3.)when to open throttle again? apex? or as soon as u see the exit or mid-corner?

4.) the s2k steering column is non-adjustable? i'm 5"7 and i'm small size

 

Yes. You don't need much speed to rev-match/heel-toe. If you're going 35mph in 3rd gear, let's say your engine will be turning 4K RPMs (just a random number). Well, if you downshift to 2nd, then the engine would be turning faster than 4K RPMs in that gear. So, you would just blip the throttle to match the engine revs to the appropriate speed for the lower gear.

Say you're going to be making a right-hand turn, and you're in 4th gear traveling 45mph. Approaching the turn, (turn on your signal, then) you start to get on the brakes (you don't have to get on them hard in a street situation). While applying the brakes, you clutch-in, blip the throttle, shift to third, clutch out. Clutch-in, blip the throttle, shift to second, clutch out. Now you're in 2nd gear, transmission is engaged, you've slowed down to the appropriate speed to take the corner, and you can immediately get back on the throttle as soon as you've "hit the apex" (try not to clip the curb, though). You weren't going very fast, but you've just had two iterations of practicing your heel-toe & rev-matching technique.
It's not highly recommended, but don't be afraid to do it if you need to. Just be prepared for the outcome. There's a lot of physics involved in racing. A couple of things to keep in mind are weight transfer and the "circle of grip". A tire has a certain amount of traction available to it, and that is commonly referred to in a diagram called the "circle of grip". If your car is not accelerating in any direction (maintaining constant speed), then it sits in the center of the "circle of grip". If you are threshold braking, then you're at the very (top) edge of the circle. If you're accelerating so quickly that your tires are almost breaking loose (not very likely in a stock S2000 on dry pavement), then you're at the very (bottom) edge of the "circle of grip". (Depending on how you visualize the circle, the directions may be reversed).

So, let's look at your question again, using a left turn as an example. If you're cornering as hard as your tires will allow while maintaining a constant speed, then you'll be on the (right) edge of the circle of grip. If you lift off the throttle, suddenly you've added another acceleration (or deceleration) factor into the mix. The addition of this negative acceleration to the existing lateral acceleration is going to put you outside the circle of grip, so you're going to exceed the amount of traction available to the tire and it's going to lose grip.

However, if you're not cornering at the edge of the circle (say you're only using 1/2 the tires' traction), then you can add some other acceleration forces (braking, throttle modulation) without exceeding the tires tractive capacity, and you'll be fine.

You also have to take into account the influence of weight transfer. The more weight you have on a tire, the more traction it has. Less weight = less traction. So, when you are cornering, there is more weight on the outside tires, so they have more traction. However, if you lift throttle in the middle of the corner, then weight transfers forward. That means an increase of traction at the front, and a decrease in traction at the rear. This often leads to what is known as "lift-throttle oversteer", and is a popular cause for spins when someone goes into a corner too hot.

Anyway, that's a lot of typing, and I know there are books/posts/whatever out there that can explain it all more clearly and eloquently than I can. So, suffice it to say that you can lift throttle in the middle of a corner... as long as you have enough extra traction to pull it off.

The optimal technique would probably be to trail brake. Basically, you want to use the tires to their full capacity at all times, so you want to ride the edge of the traction circle from maximum braking, then start releasing the brakes as you begin turning in and gradually go around the edge of the circle until you get to maximum lateral (turning) force, and then keep going around the edge of the circle until you get to maximum acceleration coming out of the corner. (this also sorta answers your third question).

A talented driver can also use trail braking to help the car rotate through a corner. You can remove weight/traction from the rear to get the tail to start coming around, and then let the car settle when you have the nose pointed the way you want to go.

Correct... the S2000 steering wheel is non-adjustable. It should be about perfect for you, though. I'm 5'9" and it's in the perfect position for me.

 

thanks a bunch for the effort on replying mxt_77 , appreciate it lots