In-car Video Lapping Shannonville Long Track

[Guillermo]

Here is the link to the in-car video I edited that shows one lap of the Shannonville Long Track during an evening lapping lapping session in August.
http://www.insightracing.ca/index.php?p=78

Let me know what you think and
any recommendations for improving my racing lines is appreciated.

[Greg F]

Re: In-car Video Lapping Shannonville Long Track

Very nice! I like the digital display too.

[fastnx]

Re: In-car Video Lapping Shannonville Long Track

Nice video. Does the regenerative braking feel any different than braking in a normal car? How many KM on your insight, and how has it been for you (as far as reliablitiy, cost to own, etc.)

As far as your lines, I would suggest in general driving in slightly deeper and turning in later in general if your car is up to it. Especially that last corner before the pit straight, compare your line to the car in front of you, you turned in much earlier, although it seemed to work, given the slow smooth power delivery (no offense). I would be in serious trouble if I turned in that early, although my car has probably double the wheel horsepower of yours. However given the nature of your car's drivetrain, I could understand how you would not want to beat too hard on it.

[Guillermo]

Re: In-car Video Lapping Shannonville Long Track

Sorry for the delay, I didn't notice this post until today.

Does the regenerative braking feel any different than braking in a normal car?

Braking feels the same, but engine braking seems a little more effective and pronounced.

How many KM on your insight, and how has it been for you (as far as reliablitiy, cost to own, etc.)

I bought my 2000 Insight used in May 2003 with 36,000 km and a lifetime fuel consumption average of 2.9 L/100Km.
Now it has 126,000 km and a lifetime fuel consumption average of 4.1 L/100km.
The only repairs done so far:
replaced thermostate
replaced secondary oxygen sensor

As far as your lines, I would suggest in general driving in slightly deeper and turning in later in general if your car is up to it. Especially that last corner before the pit straight, compare your line to the car in front of you, you turned in much earlier, although it seemed to work, given the slow smooth power delivery (no offense).

Thanks, I was trying different lines on that corner in particular.
No offense taken but the slow smooth power delivery is a result of lack of power. Keep in mind that my car has so much more grip compared to acceleration ability that it always slows down whenever I turn even at full throttle
On the track I:
1) brake hard
2) turn-in while releasing the brakes
3) full throttle as soon as the brakes are released
All of steps 1 to 3 occur within 1 or 2 seconds.

I would be in serious trouble if I turned in that early, although my car has probably double the wheel horsepower of yours.

BINGO!
For my car to get a fast exit speed, driving the correct racing line is not enough. I have to have an entry speed that allows to have a decent exit speed because i cannot accelerate in the corners even at full throttle. It's a combination of straightening out the wheel as soon as possible while carrying as much speed through the corner as possible. Krispy in his 90HP CRX is my hero at the track, he is the master at the art of getting amazing lap times driving low HP cars.

However given the nature of your car's drivetrain, I could understand how you would not want to beat too hard on it.

I bought the car used and it's paid for. If I break it badly I would buy a real sports car so i'm not too worried either way. I'm smooth and I never force the gears, other then that I do beat on it hard. I'm no stranger to 2 and 4 wheels off at the track and spinning out a few times...
It's diffecult to recover from a spin when I don't have the power to accelerate in corners. But i'm getting better at judging speeds and conditions so the frequecy of major and minor agricultural expeditions have reduced...

[malcolm]

Re: In-car Video Lapping Shannonville Long Track

your line through corner four is perfect, but you need to coast in. brake at the same spot, but let off earlier, and let the car scrub off speed all the way into the corner there. You can gain a second per lap right there (and I am not exaggerating). I used that technique through that corner in a Formula BMW, and was 7 tenths of a second faster than the other guy that was testing the car the day before (in better conditions). If you can keep the car balanced while trail-braking, that would be even better.

If you don't know calculus or physics, then ignore this paragraph. However, if you're into calculus, you might pick up that if you treat the line and speed like a parabola (obviously not exact, since it's not a hairpin), your acceleration vector is always pointing to where you want to go. Right now, you are maintaining a constant speed, so your acceleration vector is just pointing toward the axis of the corner. On an acceleration vs. distance graph, you would see the parabolic motion identified by a straight line, showing maximum acceleration through the whole corner (tangential and centripetal). However, the classic line with constant speed through the corner would result in a straight line, followed by a sinusoidal section (where you are turning at a constant speed), and then a straight line as you accelerate.


The main thing is that when you coast in, you still have roughly the same speed at the apex, but all the way leading up to the apex you are going way faster.

if you have to get on the throttle before the apex, you didn't enter the corner fast enough.


edit: by the way, your line into the last corner is perfect. going wide for that corner is a waste of time, in any car. Your video even showed proof, as you didn't lose any time on that miata, even though it has a little more power, and rwd.

[Guillermo]

Re: In-car Video Lapping Shannonville Long Track

Thanks Malcom,
I know exactly what you are talking about.
I bought the August 2004 edition of The International Journal of Racecar Engineering ($12 ouch) only because it has a fantastic article "Understanding trail braking: An engineer's guide to a much misunderstood driving technique".
I understand the theory and technique of trail braking (after reading it a second time and studying the sketches). Now that i'm more comfortable on the track I'll have to start practicing these advanced techniques.

[malcolm]

Re: In-car Video Lapping Shannonville Long Track

that's the same place I read about it too. however, I didn't read it too thoroughly until after that test I did in the FBMW, where the owner told me about the coasting-in technique. Trail-braking all the way to the apex is very difficult, and wouldn't be much better than coasting or slightly drifting to the apex (drift as in four-wheel-drift, not huge-smoky-massive-oversteer-drift-from-japan). With coasting and drifting, it's easier to control the car, because all you have to do is steer. However, with trail-braking, you need to be SUPER-sensitive with the brakes while you steer. It would be easier if you didn't have power-brakes, like in Phil Strudwick's yellow #99 Corvette.

[Boostgod]

Re: In-car Video Lapping Shannonville Long Track

cool vid G, if i could drive my car i'd give you some advice. but i think it would have been cool if in the vid where the porsche passed it said 'owned' beside the lettering cuz that thing passed hard.