PCA GT2, GT3 and Cup Car SIG - Close Call at South Bend

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Re: Close Call at South Bend

Quote:

Originally Posted by Dell (Post 941)

The line through T14 allows me to brake VERY DEEP and carry much more speed into "roller coaster". It straightens out the transition so the 2 direction change trailbrake is less of a weight shift.

The key to (T10) getting your braking and turn-in nailed down

Sorry to keep the questions coming but how do you deal with the slight left hand entry up the hill under hard braking? Do you breathe off ever so slightly to add that touch of steering and then hard on it again? Or are you already turning in when you go to the brake? Late for me is the 2 marker (2 1/2 normally). I know I can go deeper but what's holding me back is that slight turn in. I KNOW you're NOT recommending this, I am just curious how you deal with that slight turn in.

For T10, are you fully off the brake (and on the gas) before adding ANY steering? Or do you have a touch of brake as you begin turn in?

Thanks!!!!

Quote:

Originally Posted by Dell (Post 952)

T7-T8 transition-->Stay a bit further left at T7 turn-in and wait a split second longer before turning up to T8.

Can't agree more with this one. Staying left and waiting a split second works amazingly well. But at 125+MPH it takes some getting use to.

Quote:

Originally Posted by jenk12m (Post 961)

i like the woohoos!!! haha

I must be running with the wrong people....I've never WooHoo'd chasing FTS around :p

Quote:

Originally Posted by TRAKCAR (Post 944)

This is from last year 2.06's. Toyo RA1 and Pagid 29 CUP LSD.
This year I think I drove better .

Nice Peter! I regret that we didn't run together at David Murry. Next time...

Re: Close Call at South Bend

Quote:

Originally Posted by FTS (Post 969)

I'm not even going to ask... :p

Please do, no worries

Re: Close Call at South Bend

Quote:

Originally Posted by bman (Post 970)

For T10, are you fully off the brake (and on the gas) before adding ANY steering? Or do you have a touch of brake as you begin turn in?

Talking with Peter Krouse on this about my driving, he recommended starting the braking at the turn-in. I told him I'd rather play with smaller balls...::-/

Quote:

Originally Posted by bman (Post 970)

I must be running with the wrong people....I've never WooHoo'd chasing FTS around :p

Of course you are running with the wrong people, I should say "were." I WooHoo'd chasing you :D

Quote:

Originally Posted by jenk12m (Post 973)

Please do, no worries

I won't here. Hopefully I'll see you and Dell at VIR next month and we'll make a dinner conversation ;)

Re: Close Call at South Bend

Don't know if I will make it next month but I do plan on attending the PCA zone 2 club race in June. I had a blast last year and had more track time than I could handle

Re: Close Call at South Bend

There is track time during the club race, I assume for advanced drivers?

Never mind, found the info, I will put it in the calendar. Btw, if any one has events to advertise, I cannot keep up with all the track and social events that PCA puts out, let alone other clubs, please feel free to add them to the Register's calendar.

Re: Close Call at South Bend

This turned out to be a great thread, very informative. So with the risk of being an a$$, as the contrarian I am, I'll add few of my notes with no offense intended to anyone.

Quote:

Originally Posted by TRAKCAR (Post 944)

This is from last year 2.06's. Toyo RA1 and Pagid 29 CUP LSD.

How is the lock ups set up with the cup LSD?

Quote:

...Please critique, I like free coaching ;-)

I'll give my 2 cents:

T1: I don't think you are trailing the brakes enough and missed the apex on both of your fast laps. On the first lap, you also turned in too late IMHO. In my experience turning in early with very slight steering while trailing the brakes until the car attitude is right for throttle nets as much as 0.7 seconds just on the braking zone alone.
T2: for some reason you short shift to 4th gear and probably lost 0.5 secs because of that. Stay on 3rd.
T3: as others mentioned, you can turn in earlier and let it drift with speed with less steering.
T6-6a: I'd stay off the curbs there. Our friend hit the bridge during Zone 2 event, because he put the left rear on dirt on 6a and lost the control. Going over the curbs really does not add to speed or take less time that has any significance.
UpHill eSess: I used to take your line, albeit much slower. Although it is counter intuitive, adding some curves to your line while avoiding all the curbs makes the car feel more settled and much more confidence inspiring. Just wait a split sec more before your turn ins. Just like Dell describes, it works much better.
I was criticized for taking Oak Tree similar to you because I was abusing the tires and sliding the car too much for that turn. I was told by a coach to brake later after T10 and trail the brakes until the attitude of the car at Oak Tree is right and then get on gas hard. Something for you think about and to work on for me ;)
We can all brake later into T14 as Dell mentions.

Dell, I hope you don't mind if I disagree with you on couple of things ;)

Quote:

Originally Posted by Dell (Post 952)

T1-->Get tighter. All the grip is on the inside line. Also, grab second and short shift to third just after track out heading to T2. Staying in third gives back several tenths.

I've had this discussion so many times, I lost count, and it applies to several other places as a general practice for me. Your technique actually penalizes you more than providing gains. Shifting down/up is at least a 0.4-0.5 sec activity, in which you are off the gas and actually decelerating. The LongG generated in second gear is about 0.4-0.45 vs 3rd gear of about 0.35. Lifting off throttle generates a negative LongG of about 0.14 to 0.18 at that speed. So, shifting from 2nd to 3rd actually nets you a loss of about 0.1 to 0.2 secs in that corner. It feels faster, but I haven't seen any data that shows gains.

Quote:

T4-->Grab 2nd and then short shirt to 3rd on the way to T5. This will grab another few tenths.

Same point as T1 for me. Although with the GT3 having 8500 rpm it is possible to ride 2nd gear all the way past T6; however, you are adding one more shift than necessary IMHO. Taking T4 with 3rd, you can ride the throttle all the way to the bridge straight. And since you have to short shift from 2nd to 3rd in your technique, lifting off throttle turning into T5, you are not able to take full advantage of the torque that comes only at full throttle, so no gain from 2nd gear, but actually loss of few tenths.

Quote:

T14-->Grab 2nd just before the right-hander down the roller coaster and then short shift to 3rd in between T14a and T15. I've tried both and the data shows that extra burst of speed from 2nd grabs you another few tenths.

I don't think you can be on full throttle into T15 on second gear, so no torque advantage, and you are short shifting, so the net is again a loss due to shifting activity. Staying on 3rd, you can be on full throttle, full torque available and don't lift until trailing the brakes into T16.

One of the most common mistakes we make I believe is go with what feels fast without knowing what is actually fast. I am not saying this because I am fast, clearly not as much as Dell or many others, but looking at data and painstakingly analyzing every single corner. I collected so many instances of data from VIR and Summit about this 2nd vs. 3rd vs. 4th gear stuff that, to me there is no argument. But I have been proven wrong many times before ;)

darn it, where is the emoticon that hides behind a wall? Pete, we need that one buddy!

Re: Close Call at South Bend

Quote:

I'll give my 2 cents:

T1: I don't think you are trailing the brakes enough and missed the apex on both of your fast laps. On the first lap, you also turned in too late IMHO. In my experience turning in early with very slight steering while trailing the brakes until the car attitude is right for throttle nets as much as 0.7 seconds just on the braking zone alone.
T2: for some reason you short shift to 4th gear and probably lost 0.5 secs because of that. Stay on 3rd.
T3: as others mentioned, you can turn in earlier and let it drift with speed with less steering.
T6-6a: I'd stay off the curbs there. Our friend hit the bridge during Zone 2 event, because he put the left rear on dirt on 6a and lost the control. Going over the curbs really does not add to speed or take less time that has any significance.
UpHill eSess: I used to take your line, albeit much slower. Although it is counter intuitive, adding some curves to your line while avoiding all the curbs makes the car feel more settled and much more confidence inspiring. Just wait a split sec more before your turn ins. Just like Dell describes, it works much better.
I was criticized for taking Oak Tree similar to you because I was abusing the tires and sliding the car too much for that turn. I was told by a coach to brake later after T10 and trail the brakes until the attitude of the car at Oak Tree is right and then get on gas hard. Something for you think about and to work on for me ;)
We can all brake later into T14 as Dell mentions.

Thanks Fatih!
I will try to post this years lap. Slower but I think I drove better and did some of what you mention above.

Re: Close Call at South Bend

No worries disagreeing. The discussion is what fosters the best result for everybody.

Keep in mind all of my comments and suggestions are based on my 996 GT3 so it might be different for y'all with higher redline and a significant amount of more power.

As far as the 2nd versus 3rd gear I would have to find the data files but I tried it both ways and the data clearly showed I was faster. The delta between accel in 2nd + shift 3rd is faster than just accel in 3rd. There is no low end power in the GT3 and falling outside the meat of the power (up at top) you are really giving back time.

There is no way for me to take 2nd to T6 or I'd be bouncing off the rev limiter.

The T4->T5 transition was also faster in 2nd versus 3rd.

With all of that said, it is easier to take 3rd instead of 2nd in those spots since you can be WOT without all the torque of the top of the power band. But make no mistake, your accel is slower in 3rd.

Again with T14a->T15 taking 2nd is faster. I didn't believe it and had to run it both ways with data to show the time I was picking up.

I'd have to find the data files but I have countless files from VIR and finding that test file would be like finding a needle in a haystack. At least I have a project for this event! :)

Re: Close Call at South Bend

dell, did you have shorter gearing in your 996 like the current RS does. the .2RS gearing is a lot shorter than the .2 non RS.

Re: Close Call at South Bend

Man, finally someone who keeps data files and actually looks at them! :D It would be great to compare some data, even if it is 996. May be we can look at data together next month when we find the time.

I found a geek! I found a geek! :kiss:

Re: Close Call at South Bend

been known to scare people some times too. lol
http://img145.imageshack.us/img145/3...e2june0778.jpg

Re: Close Call at South Bend

naughty naughty!

:D

Re: Close Call at South Bend

haha, i didnt do it on purpose...

with all this info, i cant wait to get back to VIR

Re: Close Call at South Bend

Quote:

Originally Posted by jenk12m (Post 994)

dell, did you have shorter gearing in your 996 like the current RS does. the .2RS gearing is a lot shorter than the .2 non RS.

1st and 2nd were stock. 3rd-6th were shorter.

Quote:

Originally Posted by FTS (Post 995)

I am a total stats geek. The only way I got faster was data analysis :-8

Quote:

Originally Posted by jenk12m (Post 996)

i like me some curbs

Nice! :-DD