AC Kunos: Porsche GT3 Cup @ Road Atlanta - Monday 13 May 2019

[Miguel Batista]

How were your temps? If they got too cold, your pressures dropped so your grip goes south. Also, you could have balance issues. These cars are very bottom heavy which makes them fun but also mean that you need to brake hard so that you get weight forward or you will have understeer followed by severe oversteer once the front tires bite. And practice...

 

[Raresch]

How were your temps? If they got too cold, your pressures dropped so your grip goes south. Also, you could have balance issues. These cars are very bottom heavy which makes them fun but also mean that you need to brake hard so that you get weight forward or you will have understeer followed by severe oversteer once the front tires bite. And practice...

I see. The temps were around 70-75 which I know were low ... but the pressure was 26-25 for almost the whole race. Every time I get the pressure right, the temps drop. If I want the temps right, the pressure is just way over the line. I don't know how to setup them better.

 

[RobertR1]

@Celtic Pharaoh can you expand a bit on your rear ARB setting? Per the tool tip the arb should be lower on a track like RA due to its bumps and curbs yet yours is very high. Curious to learn how arb works for AC. Your setup felt really nice btw so thanks for sharing it.

 

[Kek700]

Hi there,

I know I am the slowest and I want to improve, so I want to ask a question, if I may. Yesterday, after 20 minutes, I was already struggling for grip. The tyres dropped almost immediately, in one lap, and even if they were in the medium grip area, I was sliding a lot more then before. Still, all the others seemed to not have this issue and seemed that you guys were having almost the same pace as before.

How can you manage tyre wear so good?

EDIT: I didn't spin until then. I think the first spun was after that, at about 25minutes from the start.

I am only speaking for myself.....
If you do not drive the car hard the tyre temps will drop along with the tyre pressures.
That for me is why I am careful when getting caught in traffic, the 911 cup being particularly
sensitive for that, my Nissan Gtr gt3 is pretty fool proof in that respect, so it does not matter
so much, but I still have to be careful.
I would like to read someone else's input to that, just out of interest.

PS, all my tyre temps were in the green, with the exception of front right, which was green for most of
the lap.

 

[Craig Dunkley]

I would like to read someone else's input to that, just out of interest.

+1 here ...When my tires started going into the blue (off green) I came of the racing line slightly going into a bend/corner, so I knew my tires had got to work harder to get me round..but mostly they were in the green, so I rarely had to resort to this method. Sometimes, no matter how hard you push her they will remain cold, but you work all this out in practice..one other thing, every car is different and how you setup the car can make a huge difference ...I only managed to do around 11 laps, so maybe I should shut up.

 

[Chris Down]

Hi there,

I know I am the slowest and I want to improve, so I want to ask a question, if I may. Yesterday, after 20 minutes, I was already struggling for grip. The tyres dropped almost immediately, in one lap, and even if they were in the medium grip area, I was sliding a lot more then before. Still, all the others seemed to not have this issue and seemed that you guys were having almost the same pace as before.

How can you manage tyre wear so good?

EDIT: I didn't spin until then. I think the first spun was after that, at about 25minutes from the start.

Hey! Some possibilities:

• Are you running really low rear wing? Maybe you are sliding through the corners more, and would have better tyre wear with more rear wing. More rear wing may also make low chemical grip situations more tolerable at speed.
• It could also be made worse by wheelspin if you are not controlling the throttle on corner exit.
• It could also be not making best use of the contact patch, ie. running with the wrong camber settings, which makes low chemical grip even worse. Looking at tyre temperature and evenness may help you to work out how to maximise the contact patch.

That said, I think after about 20-25 minutes, most of us were certainly feeling some tyre wear as well. It's just a question of how much

 

[Raresch]

Hey! Some possibilities:

• Are you running really low rear wing? Maybe you are sliding through the corners more, and would have better tyre wear with more rear wing. More rear wing may also make low chemical grip situations more tolerable at speed.
• It could also be made worse by wheelspin if you are not controlling the throttle on corner exit.
• It could also be not making best use of the contact patch, ie. running with the wrong camber settings, which makes low chemical grip even worse. Looking at tyre temperature and evenness may help you to work out how to maximise the contact patch.

That said, I think after about 20-25 minutes, most of us were certainly feeling some tyre wear as well. It's just a question of how much

hey, thanks for the reply.

• The wing was actually pretty high, at 6 I think.
• Wheelspin control ... that might be something ... but there was no screeching sound ... but surely i an not that good at this either.
• Yeah. I didn't messed with camber too much, I don't really know how to change it. There is a setup guide on the forum with multiple points that I try to follow, but sometimes it just doesn't work ... I managed to get a good feel for the rear camber, but I didn't have time for the front one.

 

[Kek700]

Just looked at the two setup's posted on this post, looking to see if I could come to some sort of
similarity between mine ( mid fielder ) and the other two front running drivers.
Considering that the setup is limited for this car, surprised to find all the setup's are miles apart.
They are really nothing alike, apart from tyre temp's

 

[Kek700]

@Raresch followed you for a few laps, your driving was certainly quick enough not to have
tyre problems.
Perhaps when you started to get inconsistent laps after lap 14, you did not think to get your tyres up to temperature before you started to push.
You could post your setup, just in case you have done something really wrong?

 

[Raresch]

@Raresch followed you for a few laps, your driving was certainly quick enough not to have
tyre problems.
Perhaps when you started to get inconsistent laps after lap 14, you did not think to get your tyres up to temperature before you started to push.
You could post your setup, just in case you have done something really wrong?

I will post the laps, but most certainly is all over the place. Well, I was pushing as always and then, suddenly, after 20 minutes from the start I started to miss apexes and I felt like sliding out of the turn, needing to rotate harder the wheel. Maybe it was less fuel as well, but it was really weird because it happened really sudden. after I started struggling, mostly in the rapid chicanes downhill and at the end of the downhill straight, were you have 2 right turns, before going to the third and last straight (which isn't that straight anyway ) )

 

[Raresch]

I think this is the one I used. I know it's broken because I don't really know where to start. I usually start with what is set already. I didn't test the other 2 setups posted here. hope is not that bad, but it might be

 

[Reik Major]

Just looked at the two setup's posted on this post, looking to see if I could come to some sort of
similarity between mine ( mid fielder ) and the other two front running drivers.
Considering that the setup is limited for this car, surprised to find all the setup's are miles apart.
They are really nothing alike, apart from tyre temp's

Well, I often doubt myself if the setups I make are good or make sense from a physical point of view.

Over the years I got an idea what change might do what. So my setups are trial and error in terms of what feels better and what doesn't. For me it often results in setups which are tricky to handle but finally fast. Very often a change makes the car feel easier to handle but makes me slower, so I go for the risk then...

But in general I don't know what I'm doing really.

 

[Kek700]

@Raresch
After being able to look at two drivers setup's, who quite a bit quicker than I.
I don't feel too awkward in suggesting the following. I am assuming you are of a similar standard to me.
Perhaps tyre pressures 1 psi too high on the left side of the car. certainly "too" much camber
on the front and rear.
You could run more rear wing, to give the car a bit more confidence in some corners.
( for you and me that counts more than gaining 5 meters at the end of the long straight ).
And even that is dubious.
I ran 0.22 toe on the rear, again for more confidence out of some corners.
The car certainly does not mind that much rear toe.
If you lost some concentration at lap 14, with the tyres at 1 psi more than they should be on the
left side of the car.
I can see why this may have escalated into an ill handling car, but your setup looks ok.
I would suggest more, but as there is so much conflict with the setup's ( including mine )
that i have seen, your setup is arguably sound.
Apart from tyres and camber.

 

[Kek700]

Well, I often doubt myself if the setups I make are good or make sense from a physical point of view.

Over the years I got an idea what change might do what. So my setups are trial and error in terms of what feels better and what doesn't. For me it often results in setups which are tricky to handle but finally fast. Very often a change makes the car feel easier to handle but makes me slower, so I go for the risk then...

But in general I don't know what I'm doing really.

But you do if you are quicker, that what counts, like you, but the opposite way around, I can be quicker
with some of my setups but I always go for a safe handling car.
As I am in the middle of the field, a few tenths here or there is of no concern to me.

 

[RobertR1]

fyi, real race pace is about 3 seconds a lap slower: https://porschegt3cupusa.imsa.com/schedule-results/current-results?event_id=73

You basically can't do a full throttle coming down the hill into the last corner, the lift on the left hander after the cresting T3 is a lot more severe and you can't barrel down the esses as fast. The braking is earlier also. 3 seconds on a short lap is a lot.

 

[RasmusP]

I promised you the guide when I'd have completed it. Here is the first version

https://www.racedepartment.com/threads/basic-nordschleife-guide-wip.168525/

 

[Medilloni]

Do you have project cars 1 or 2? If so, that's how I learnt the track back then:
Go into hotlap mode, select one of the three Nordschleife Sectors and select 3 ghosts that are 1,2,3 seconds quicker than you. For the beginning just pick P10, P50 and P100 or something.

Then you follow the quicker cars through the sectors. Do one sector until you learnt it.
Then you select the next sector and do the same.
When you know all 3 sectors you try the whole lap

You need to learn the track in patterns. Once you've built a basic knowledge of the track you'll start to see these patterns.

Now it really goes off-topic... Craig, feel free to move this post to the Nordschleife Thread once you created it
I always wanted to write this all down. Perfect opportunity since John asked!

Here are my "bridges" for the patterns and also a description of what I have in my head:
- T1: very sharp, very slow, stay on the brakes until you clip the inside kerb and then go for a good exit

- T2: 4th gear 50% throttle right hander. Turn in a bit too early and take the outside kerb to the limit

- T3+4: brake on the straight, lift brakes, do the left hander. Full brake again, lift brakes, do the right hander.

- T5+6: first pattern starts: left, brake, right inside kerb carefully, full throttle left. Brake, right inside kerb carefully, full throttle left.

----- Hatzenbach completed -----

- Flugplatz double right hander: slowly and carefully lift your throttle to bring a bit weight to the front. Turn in slowly and carefully to not overuse the fronts. The moment you start to turn, back on throttle!

- Schwedenkreuz left hand with bump: slooowly lift the throttle and turn in way too early. When the bump comes open the steering and go slightly back on throttle to not risk a drift!

- Aremberg: (Pattern 1: tight right hander after full throttle, clipping the inside kerb)
Brake when the tarmac patch colour changes! Stay in 3rd gear and try to "roll" until the apex. Don't try to go the ideal line from the outside. Just clip the inside kerb and go early back on throttle without touching the outside kerb!

- Fuchsröhre: just go as straight as possible

- Adenauer Forst, end of Sector 1: You fly up the hill with 270 km/h. Start to brake in the middle of the uphill straight!
Lift the brakes before turning in or you'll wipe out!
Aim for the inside kerb, take it fully. The moment you have all 4 tyres stable again, BRAKE!!
2 gears down to 3rd, lift the brakes, roll through the right hander on the very inside.
Go back on throttle and let the car move to the left. Aim for the trees. For real, aim for the trees lol.
When you see the left hander coming close, brake in a straight line and brake into the trees.
Brake, brake, brake, then turn in while still braking and just trust the car.
Keep turning and bring the car around the left inside kerb so you'll end up on the very left for the following 90° right!
Lift the throttle, aim for a late apex for the right hander and as early on the throttle as possible!

--- End of Sector 1---

- Metzgesfeld: double left hander, very fast (Pattern 2). Important to not have too much weight shifting!
Brake a little, down 1 gear to 4th. Lift the brakes and go around on the very inside, use the cambered track and roll through it with 70% throttle!

Then once the car is straight again, brake for the left hander (Pattern 3). It's important to not hit the inside kerb here but also to stay on the very inside! Trailbrake to the apex until the oversteer hits you. Go back on throttle and go uphill in a straight line, trusting the exit!
Pattern: uphill 90° right with oversteer at the exit

- Kallenhard right right hander: pattern (1&3) similar to Aremberg and mirrored version of the left hander before.
Brake very very early, down to 2nd gear! stay at the inside, use the cambered track! Be careful for oversteer and the kerb at the exit!

- Spiegelkurve: repetition of the of Metzgesfeld (Pattern 3) but this time without braking. Swing the car around, go as tightly as you can for the inside!

- 3 fach rechts, triple right hand: repetition of the double left hander, Pattern 2. Brake a little, then go back to about 50% throttle and carefully try to roll as fast as it gets through all 3 right handers.
Back on throttle until you see the right hander coming close. Brake a bit later than you want to!

- Wehrseifen: After you tapped the brakes later than you would've liked to, give a push to the throttle gain to get a bit of speed. Then once the mini straight comes, BRAAAAAKKKKEEEEEE!
Extremely tight left hairpin. 2nd gear!
Brake and brake and brake and try to get a bit to the middle of the track. Aim for a late apex of the left hander and back on throttle.
This corner reminds me of the left hander of Adenauer Forst where you aim for the trees.
Also this is pattern 4.
Last corner is a 90° right hander (Pattern 1&3), similar to Kallenhard. Early on the throttle, stay at the inside but there will be some oversteer happening at the exit!

- Breidscheid: Pattern 4, similar to Wehrseifen. Mini straight and into a very tight double apex left hander. Brake earlier than you want to!!!!
Brake, brake and brake again.
Understeer to the inside and pray you're not hitting the outside kerb+wall but also hope you're fast enough to not lose a full second...

- Ex Mühle: Another 90° right hander, yay! Pattern 1&3. Stay at the inside, early on throttle, oversteer will happen at the exit!

- Bergwerk: Brake about at the middle of the straight after the slight left kink. Again, Pattern 1&3. Stay at the inside, early on throttle, oversteer will happen at the exit!

FFFFUUUUULLLLL THHHRRROOOTTTLLLEEEE PPAAAARRTTTT

Stay in 5th gear and mash that f*cker into the rev limit! If you really hit the rev limit raise the gear ratio of 5th gear
It's left left left, right right. A slight left and you'll see a bend to the left.

- Mutkurve: No pattern here, only praying! You brake as late as possible, only a tab while actually keeping the foot on the throttle! You shift down to 4th and hope it will get in and then you lift the left foot, put the pedal to the metal right at the left hand kerb and hammer through that corner.
Goal is 220 km/h but everything above 200 km/h is balls to the walls so... yeah!
- Klostertal: Following right hander: lift to about 70% of throttle, turn in, put the foot down again.

- Steilstrecke: You aim for the left hand kerb that sticks out a bit. Brake when you pass this little part that sticks out. Brake while keeping the car at the very left side.
Hold the brakes! The car will automatically move to the right hand though, aim for the inside again!
Half and carefully on the throttle, drift the car through this strange right hander. Oversteer will happen!

---- somewhere around here Sector 2 ends!---

- Karussell: Right before you see it there's a sticking out kerb at the right like for Steilstrecke. Hammer down the brakes right before passing this part of the kerb!
You'll see the car moving to the middle of the road and the concrete inside starting on your left. Wait a little before turning in and jumping into it. You lift the brakes but don't push the throttle. Roll with about 10% throttle into the concrete cambered part!
Hold the steering wheel at about 90° and try to not hit the inside while not getting spit out!
Play with the throttle to keep the line. Turning won't help much here...
Then when you see the tiniest bit of straightening up again, PUSH DOWN THE THROTTLE!!!
You won't be able to hold the car inside of the concrete but you won't need to. You'll get spit out right to the next apex!

- Uphill double left: Not a real pattern here, just clip the 4th gear and turn in to the second left hander similar to Spiegelkurve! Down to 3rd gear and don't hit any kerbs. Just run through this in the middle of the road!

- Hohe Acht: You fly uphill in 3rd gear. Brake and turn in way too slowly! You'll hit the inside kerb if you turn in normally. Like I did in my video!
Roll through it, don't hit a kerb!

Now a repetition starts. I'll write up the whole repetition part now so you'll see it when watching:

3rd right, 4th straight, 4th right, 4th left+right (clip the kerbs!).
3rd right, 4th straight, 3rd left+right (NO kerbs!).
3rd right.

You have 2x a "slow" right hander following a downhill left+right combination. First time is fast, second time is slow.

Then Eiskurve: Brake a bit early, keep it to the inside and again, aim for the trees!
Once you see the exit in the middle of your windscreen you just put your foot down and open the steering wheel. You'll mash over the right hand kerb and "cut the exit".
Mostly the car will oversteer on the throttle at the apex so you'll just open the steering to counter the drift and the car will move across the exit kerb.

- Pflanzgarten 1: Full throttle downhill, brake right after the jump but go back to a little bit of throttle to catch the rear! Double right hander like the double left handers in Sector 2! Wehrseifen and Breidscheid!
Full throttle in 4th gear from there.

- Pflanzgarten 2: Another left handed downhill jump! This time you don't brake, just keep the throttle pinned! Now similar to "Eiskurve" you do the right hander, open up the steering and hit the left kerb while going straight.
Then the Stefan Bellof S appears. It's a direct repetition. Right hander, open steering, go over the left kerb.

- Schwalbenschwanz: This is a very complex corner... The first right hander is similar to Metzgesfeld and 3 fach rechts. You brake, lift a little and try to keep the grip on all 4 wheels without major weight shifting. Keep a bit of trailbraking and throttle together to make it quickly through this right hander.
You'll have to brake a bit earlier than you'd think while staying in the middle of the road!

90° left hander: You approach it from the middle or the right, brake a little but not too much or you'll lose the rear! Aim for the inside but rather for the middle really.. difficult corner! I hit the inside in the video...
Big fat scary kerb on the exit. I take it but you really shouldn't... If you crash here you'll lose a lot of time!
This corner is a massive mix of understeer and oversteer. Just try to steer through it, a bit slower rather than too fast!

- Kleines Karussell: Similar to the big one, you go into it a bit later than you'd think and accelerate a lot early than you'd want to!
Approach it from the middle of the road, brake, stay in 3rd and roll through it. When it catches you, go for the throttle and let it spit you out!

- Galgenkopf: Very very difficult corner. Lot of time to be gained or lost here!
You approach it from 4th gear, middle of the road. Brake a little but not too much. Just a love tap!
Keep it to the inside but DO NOT HIT THE INSIDE KERB!
And full throttle from here!!
Now for the last right hander you come from uphill.
Keep it to the veeeeerryyyy left right at the hilltop.
Once it starts to go downhill TURN IN!!!!!! But: wait a little, lol!
No for real, you see it going downhill while being at the hilltop and you start to turn in a liiiitttle bit. Then you'll see the the kerb starting at the right inside. The moment you even see a pixel of this TURN IN!
You'll just miss the inside kerb due to understeer when it really goes downhill. Keep it at the front end grip limit, stay at the inside and keep the right foot planted!
You'll think you won't make it and will crash to the left outside at the exit but.. You don't
Once you are past the apex open the steering and off you go to the long straight!

- Tiergarten (almost done!): It's balls, balls and balls. After the left kink, lift the throttle and roll through the left/right! (8:14 in the vid).
Then BRRRAAAAKKKKEEEE!!!!!!
Down to 4th, shoot past the inside armco and pray. Lift the brakes to not cause oversteering at the apex and BRAKE AGAIN!!!!!
Down to 2nd, go slightly across the right inside kerb and hammer down the throttle!
Try not to hit the outside barrier when entering the GP circuit.

---- Lap done----

Overall this track is mainly: staying at the inside, oversteer at the exit, a few repetitive flows, a few fast long bends where you need to keep the weight shift under control and a few times remembering to brake late or early to not crash.

Do the sectors separately if you have pcars 1/2. Read my notes and watch my video so you can try to figure out the patterns I mention. After some time things will clear up in your head and then the fun starts!
The easiest cars around here: Mclaren 650s GT3 with massively softened rear springs and the Z4 just with lowered rear wing.
Audi is difficult and stiff, MB AMG is spongy and difficult due to springing around, Nissan is too understeery, Porsche is nice but melts the rear tyres, SCG is kinda nice but difficult to get fast and the Ferrari is balanced but has a few weird corners like Flugplatz where you'll do a massive wheely!
I'm using the Lambo with a secret setup (sorry). Stock setup is very difficult.
The easiest are definitely the Z4 and Mclaren!

I attached my setups for the 650s

Here's the vid:

At the end, this is my full "remembering" words while actually driving. You should write down something similar while practicing or watching a video:

Hatzenbach:
- T1: tight tight tight, early braking, early throttle
- T2: throttle, 4th, concentrate on entry steering
- T3+4: brake, steer, brake, steer
- Left, Right kerb, left. Brake, right kerb, left

Flugplatz double right:
- slooooowly lifting, sloooowly turn in, throttle throttle throttle

---whatever, throttle---
Schwedenkreuz:
- slight lift, early turn in, carefully back on throttle for stabilizing!

Aremberg:
- Tarmac colour!
- brake brake brake, INSIDE, 3rd, throttle!

Fuchsröhre: whatever, bump, bump

Adenauer Forst:
- uphill, oh ****. Tap brakes, turn in, throttle, brake, 3rd.
- trees trees trees, brake and turn blindly for late apex
- not that fecking inside kerb again!

Metzgesfeld:
- a biiiiiiit slowing down, double left, beware of the outside!
- oh **** this left hander... Down to 2nd and nail the cambering!

Kallenhard:
- brake eeeeaaaarrrly, do not shift into 4th!
- inside inside inside

Spiegelkurve:
- full throttle... oh crap... turn in early and fly through the cambering!

3 fach rechts:
- caaaarreeefuuulllyyyyyy

Wehrseifen:
- first slow left repetition!
- brake, straight, brake, 2nd
- laaaaate apex

Breidscheid:
- second slow left
- brake early... brake early...
- laaaate apex

Ex Mühle:
- oh crap the 90° oversteery right hander nr. xy

Bergwerk:
- wait, this is not the full throttle part!
- brrrrrrrrrrake!
- another oversteery right hander, yay

Now this is the full throttle part!
....don't shift into 6th!....

Mutkurve:
- brake, 4th, throttle, pray

Klostertal:
- full throttle! naaah, a slight lift

Steilstrecke:
- standing out kerb on the left... standing out kerb on the left...
- BRAKE!
- keep it to the right..... aaand drifting time!

Karussell:
- standing out kerb on the right...
- braaaaake
- wait
- now into that bloody thing!
- stay in... stay in... stay in...
- enough, full throttle!! (oh please not too early)

Double left hander:
- 4th.. 4th....
- do not hit the inside kerbs and brake when it's stable down to 3rd!

Hohe Acht:
- crap I'm gonna die!
- wohoo, didn't crash
- alright, downhill, 3rd, repetition starts!

Right hander in 4th:
- stay on the throttle.. I'm gonna die.. stay on the damn throttle!

Wippermann, left hander:
- stay in 4th, keep the momentum, hit all the kerbs!
Right hander:
- OVER THE KERB! Better lift to not spin...

- alright, next slow right hander, 3rd gear!
- I'm gonna die... yes, there's the exit kerb for me!

Eschbach:
- slow repetition! 3rd gear, keep the momentum!
- left left left left left
- no kerbs this time!

Brünnchen:
- stay in 3rd.. oversteery exit.. keep momentum!

Eiskurve:
- 90° left, trust the exit kerb. Just go straight lol
- SUUIICCIIIDDEEEEE
- made it

Pflanzgarten 1:
- brake!, slooowly lift the brakes, a bit of throttle to keep the rear down!
- hooolllyyy fffffff****** THROTTTTLLLEEE

Until the right hander:
- throttle, throttle, throttle. Steer right, hit the kerb on the left, steer right, hit the kerb on the left!

Schwalbenschwanz:
- bbbrrraaaakkeee, BUT NOT TOO MUCH!
- steer carefully.. not lose the rear.. not be too fast...
left hander:
- caarreeefffuully brake and go around. Do not touch the kerbs!
- feck, hit both kerbs...

Kleines Karussell:
- stick to 3rd!
- brake a little, dive in lately!
- THROTTLEEEEEEE

Galgenkopf:
- little touch on the brakes, keep the speed. Oh feck this is too fast...!
- made it!
- To the leeeeeeft, hilltop.. wait, wait, wait!
DOWNHILL! TURN IN!
- don't turn in too quickly!
- the right kerb comes.... I'll just turn in already, oh there it is, yeehaa!

Exit of Galgenkopf:
- keep the steering.. understeer... feck... I'm gonna crash...
*cambering pulling you at the exit*
- I'm alive!

Döttinger Höhe into the last chicane:
- do not brake.. do not brake...
- automatically lift for the scary right hander!
- bbbrrrraaaakkkkeeeee
- lift and hit the left armco!
*oh feck that was close*
- bbbrrrraaakkkeeee
- 2nd, inside kerb, full throttle. Please don't spin!
- oops, the outside armco came close
- Finish!

Hey Rasmus, now that I've managed to complete about 6 clean laps (seriously! lost count of the times I've gone off) I've re-read this post and can't believe how accurate it is, and bloody hilarious Thanks again buddy!

 

[Medilloni]

Edit: I made a daft post, didn't read the setup properly