AC GT3 @ Zandvoort - Sunday 31st January 2021

[Kek700]

Strange , would never have assumed it was the floor. Never experienced any handling issues, just assumed it was bump stops, which makes sense, you would assume that was the last thing to occur, stopping it from grounding.
Always assumed downforce and bump stops were integral to Gt3 down force.
Basically there to stop the downforce from stalling, which would happen if the under try grounded.

Why is all this so confusing.

 

[RasmusP]

Strange , would never have assumed it was the floor. Never experienced any handling issues, just assumed it was bump stops, which makes sense, you would assume that was the last thing to occur, stopping it from grounding.
Always assumed downforce and bump stops were integral to Gt3 down force.
Basically there to stop the downforce from stalling, which would happen if the under try grounded.

Why is all this so confusing.

Not that confusing:
If you here the scraping sound, you either raise ride height or raise the bump stops (lower suspension travel) until you don't hear it anymore.
I'm not sure what sound they would make then... Maybe none.

A bit of scraping isn't too bad though, f1 cars do it on every straight as we all know from the sparks

In theory you could record a lap with the "aero" or "wings" app open. Sadly you can't record this and motec ride height is a bit bugged btw...

Then watch your record (doesn't work in replay either...) and check the lift and drag values.
Also open the suspension app I think. You can see the ride height there.

When you hear the scraping sound, one of the lift values from the aero should instantly drop to 0. Diffuser or front splitter.

When you hit the bump stop, the suspension movement should stop before hitting 0 and the aero should continue to show a lift value.

Afaik the ride height is displayed a constantly drawn line with a fixed line in the graph, which shows the road level.

Fun fact: when it's below 0 and you're in the tatuus, your race is over. Beached
I know all this from running the tatuus events in... 2018?
Good times hehe

 

[Interslice]

Strange , would never have assumed it was the floor. Never experienced any handling issues, just assumed it was bump stops, which makes sense, you would assume that was the last thing to occur, stopping it from grounding.
Always assumed downforce and bump stops were integral to Gt3 down force.
Basically there to stop the downforce from stalling, which would happen if the under try grounded.

Why is all this so confusing.

It's an odd sound effect. More like engine failure than the floor scraping. I now from my irl car when the the sump guard hits the ground on bumby roads there's no great drama, just a scraping noise. Flat through eau rouge in gt3 911 it could be a different story

 

[Kek700]

@RasmusP
Thanks for that, followed it all, so tomorrow I will have a go at what you said.
Familiar with all of that, so it should be easy enough to try and put into practice.
I have always meant to look into bump stops and their effectiveness, this is a good excuse.

 

[RasmusP]

@RasmusP
Thanks for that, followed it all, so tomorrow I will have a go at what you said.
Familiar with all of that, so it should be easy enough to try and put into practice.
I have always meant to look into bump stops and their effectiveness, this is a good excuse.

Matteo and Phils had a good discussion about cars bottoming out at Barcelona and how to control ist in the gt3 mugello setup thread.

I'll check if I'll find a quote...
Edit:
No quotes but read from here:

GT3 Car Pack @Mugello

Been thinking of doing this for a while so here it is. Base setups for the current relevant GT3 field. I used Mugello. The track has everything, big braking zone, slow corners, direction changes, fast corners, off camber corners...the setups that work well here should work well everywhere. The...

www.racedepartment.com

 

[Medilloni]

Pls can you put me in as a reserve with the 488 @Chris Down , will try and make it, and thanks for organising!

 

[random2k4]

How many laps are we looking for. (my calculations are about 38) Never raced at this track before and just realized softs melt like crazy. Just need to know a good time to pit now

 

[Henri Sinik]

Sign me up, 650S

 

[pattikins]

How many laps are we looking for. (my calculations are about 38) Never raced at this track before and just realized softs melt like crazy. Just need to know a good time to pit now

In the last race that I did @ Zandvoort, back in 2019, we did 36 laps. The race winner (Tariq), however, like everyone else, left the track a few times. Even with all the s signed up for this race, I don't think it's going to be any more than 37 laps.

Edit: After seeing this:

I may have to revise my calculations .

 

[Kek700]

@random2k4

last time here 36 laps, I did two pit stops, I was competitive when I was on the track, but spent most of my time in the pits, not one of my finest moments.

@RasmusP @Interslice

Did some time in the Porsche, it is not the packers, as said by you more knowledgeable here, best guess I can make is undertray, front and back.
From what I can see, does not seem to affect DF. But as I am looking at numbers and not a graphical representation, difficult to ascertain if there is an instant value or not.

Learnt about packers, got no useful information from my efforts, nothing new there then.

 

[RasmusP]

@random2k4

last time here 36 laps, I did two pit stops, I was competitive when I was on the track, but spent most of my time in the pits, not one of my finest moments.

@RasmusP @Interslice

Did some time in the Porsche, it is not the packers, as said by you more knowledgeable here, best guess I can make is undertray, front and back.
From what I can see, does not seem to affect DF. But as I am looking at
numbers and not a graphical representation, difficult to ascertain if there
is an instant value or not.

Learnt about packers, got no useful information from my efforts, nothing new there then.

If you don't lose control from spontaneous aero stalls, then don't bother setting anything up differently!
Aero stalls won't make you slower so as long as you're not losing control or getting a longer braking distance, it's fine.

To really see it, you would have to record your live driving and then look for the scraping sound in the video and go frame by frame.

I'd say you could lower the car until you get issues or become slower.
In theory it should make you faster until it won't work anymore..

Now that I'm thinking about it: I should look into it too haha.
Phil's mugello setups are pretty high...

 

[Goblin616]

If you don't lose control from spontaneous aero stalls, then don't bother setting anything up differently!
Aero stalls won't make you slower so as long as you're not losing control or getting a longer braking distance, it's fine.

To really see it, you would have to record your live driving and then look for the scraping sound in the video and go frame by frame.

I'd say you could lower the car until you get issues or become slower.
In theory it should make you faster until it won't work anymore..

Now that I'm thinking about it: I should look into it too haha.
Phil's mugello setups are pretty high...

I'm riding higher than usual for the clearance. It doesn't seem to affect my times because of how bumpy it is, and a low DF track.

 

[Interslice]

@random2k4

last time here 36 laps, I did two pit stops, I was competitive when I was on the track, but spent most of my time in the pits, not one of my finest moments.

@RasmusP @Interslice

Did some time in the Porsche, it is not the packers, as said by you more knowledgeable here, best guess I can make is undertray, front and back.
From what I can see, does not seem to affect DF. But as I am looking at
numbers and not a graphical representation, difficult to ascertain if there
is an instant value or not.

Learnt about packers, got no useful information from my efforts, nothing new there then.

Floor pan hitting the ground* could cause a spilt second loss of grip from the sudden increase of pressure under the car. As it rebounds you get a vacuum and an increase in aero and a sudden return of grip before it go back to normal. This translates to a wobble through eau rouge or a similar high aero corner where the whole of the car under tray bottoms out and squeezes the air beneath. If you over correct the slpit second slide it could be game over.

At slower speed corners its more of a mechanical effect and it usually the front wing splitter on the outside of the corner. This can sort of catch in the ground and cause a little bit of under steer by supporting the weight of the car that is normally used by the tyre. Again over correction can cause issues when the grip comes back.

*Just how i think about it all and no data whatsoever to back this up!

 

[Shakunee]

Sign me up please, 650S

 

[thom462]

Please sign me in. car tbd, thanks

 

[Chris Down]

Hi Chris, Ill take the 650s please.

It seems I'll have to grab the last place as long as it's still available. @Chris Down are you willing to give me the time to test the Z4 tomorrow as per @HF2000 suggestion, before deciding which car to get for the race?

Pls can you put me in as a reserve with the 488 @Chris Down , will try and make it, and thanks for organising!

Sign me up, 650S

Sign me up please, 650S

Please sign me in. car tbd, thanks

Welcome folks! Good to see you back @Henri

 

[maxilogan]

@Chris Down sorry to bother you, but this afternoon I practiced a lot with the 650s as I tested the Z4 this morning and never been able to feel "at home" as I do in the McLaren. If this isn't too much of an hassle, then, I would like to jump back in the British car, with it I've been able to brake the 1.41 wall of a few cents of a second and consistently lap on the low 1.41 in medium tyres and quite full tank, I hope it will be enough for some battle in the midfield, otherwise I'll just cruise and relax in the last spots
As a side note, my computer crashed badly and I had to somewhat restore the AC install; I'm now unable to disable (...) the wheel and driver's hands in cockpit view. Is anybody willing to help?

 

[Kek700]

Just do a steam software integrity check for AC, if there are any missing or corrupted files, should sort it .

 

[Luca Badin]

As a side note, my computer crashed badly and I had to somewhat restore the AC install; I'm now unable to disable (...) the wheel and driver's hands in cockpit view. Is anybody willing to help?

Do you mean you can't find the menu option, or does the option not make any difference ingame?

 

[uvraver]

Sorry Chris have to pull out
not this weekend
have fun