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venquessa
04-09-2018, 19:23
GT4. Used to be super sweet. Now they are broken again.

The Aston Martin in the wet is beautiful. Easy to balance with oversteer and understeer on demand, good lap times. Exactly the same set up when it's dry on hard slicks and I have super market trolley wheels on the back. Totally undrivable, even when I manage to hang it together long enough to get the tyres heated up, which was very difficult.

It's fine on softs, but they overheat.

On hards I have moved the entire setup to understeer, but holding neutral throttle in a corner the the tail just comes round.

Same setup on wets and it's undrivable due to understeer as it should be.

So what happened to the tyres again guys?

It's getting tiresome (sorry for the pun), but the trust is going. No point playing a simulation if it's all over the place with bugs left right and centre, no way you can know if you are learning a tricky car/track or just some dumb tricky bugs.

Tank621
04-09-2018, 19:36
When did you notice this change? there hasn't been an update since June

venquessa
04-09-2018, 19:53
When did you notice this change? there hasn't been an update since June

I've narrowed it down to the hard tyre. Softs work, but overheat, wets work, hards are undrivable with oversteer that's impossible, it seems to tune out.

Thetalon
04-09-2018, 22:17
Sounds kinda like the light sports cars, the radical. Insanely easy to drive on wets whether youre in the rain or dry. As soon as you put slicks on the car is almost undrivable in comparison. Constantly wants to spin and just doesnt feel like its even the same car. Balance is totally off. Its nothing new though. It (the radical) has been that way for ages. I remember the gt4 used to have the issue as well but they eventually fixed it, has it returned again?

satco1066
05-09-2018, 01:20
this message is a hoax.
Since 3 months no patch. So how can something be broken AGAIN.
Against what state, patch version or some bad dream????

venquessa
05-09-2018, 06:45
this message is a hoax.
Since 3 months no patch. So how can something be broken AGAIN.
Against what state, patch version or some bad dream????

My apologies on the "AGAIN". The reason for this is the first time I did the GT4 championship I used softs as I had not worked out the hards were the faster tyre. The issue is with the hard tyre destroys the balance of the car completely.

So, further testing, which I would encourage you to do yourself.

Aston Martin GT4, Silverstone, dry, track temp 25*C. Default loose setup, wets or softs. Drives like perfectly fine.

Now switch to hards, leaving the setup as is. It's uncontrollable.

Switch to the default "stable" setup and try again on the hards. Now it's just about drivable with a load of oversteer, but managable. Actually quite fun. You do need a couple of laps to warm the hards up though.

Switch to softs with the stable setup and it's understeer city.

There is far, far too much balance difference between the tyres.

This is not the only car that suffers this issue. The Formula C's are next to impossible on slicks but fine on wets.

Were you to attempt a wet->dry race where you can't change the setup, you would need to take softs at the pit stop, if you took hards you race would be over.

Bealdor
05-09-2018, 06:49
Aston Martin GT4, Silverstone, dry, track temp 25*C. Default loose setup, wets or softs. Drives like perfectly fine.

Now switch to hards, leaving the setup as is. It's uncontrollable.

There's your issue, 25°C is much too cold for hard tires. You won't get any heat into them.

justonce68
05-09-2018, 07:28
25' C too cold for hard's buddy

venquessa
05-09-2018, 19:36
Obviously I have a fridge under the car that keep the rear tyres cooler then. Surely all 4 tyres should get equal loss of grip if it was temperature related. The balance should remain roughly the same.

Also. Bear in mind that at race start the tyres are already heated. Yet the car is still undrivable on hard tyres. I had the telemetry HUD up and the hards where in the 70s and 80s.

Anyway, I restarted the career race at Silverstone on softs. Lap 1 and 2 I was moving up the field. Lap 3 my front left started overheating and understeering. Lap 4 my rear left started overheating and oversteering. 100+ degrees C.

My pace dropped off, half a second to 1 second a lap or so, to were the AI in front sailed off into the distance. Those behind me pestered me for 15 minutes until one of them punted me round in the final corner and I quit in frustration.

Obviously the AI don't suffer tyre temp issues, thus making this pointless in single player. I can turn the AI down, but, sure I could just turn them down to 0 and win all the races.

It just feels fake. It feels like I'm not learning/experiencing driving a simulated racing car, I'm learning how to work around Project Car tyre issues.

I know it's not all cars or all tracks, but when you are trying to do a career race and it turns out to be one with issues and the AI don't suffer it, what do you do? Retire to pits, hope you can make it up next race?

/frustrated.

Cholton82
05-09-2018, 21:18
What pressures are you running when hot ? Out of interest I had a quick go in the GT4 Aston at Silverstone with similar track temps and on Hard tyres it felt nervous for sure but then I only got them up to around 70 -80 degrees so not hot enough as they seem to work best for me around 90 degrees .
On the softs the car felt great with temps around the 80 degree mark which I maintained for around 10 laps before I got bored.

hkraft300
06-09-2018, 01:29
Obviously I have a fridge under the car that keep the rear tyres cooler then. Surely all 4 tyres should get equal loss of grip if it was temperature related. The balance should remain roughly the same.

Wrong. A car on sticky tires might feel neutral even if it is slightly over/understeer balanced. Under slippery conditions the balance issue is amplified, especially assuming you're over-driving the car trying to keep with your opponents.


Also. Bear in mind that at race start the tyres are already heated. Yet the car is still undrivable on hard tyres. I had the telemetry HUD up and the hards where in the 70s and 80s.

As stated many times already that's too cold for hard tires for optimal grip.


Obviously the AI don't suffer tyre temp issues, thus making this pointless in single player. I can turn the AI down, but, sure I could just turn them down to 0 and win all the races.

Or you could solve your tire issues, or drive within the limits of the vehicle, or reduce the AI just a little instead of 0, or...


It just feels fake. It feels like I'm not learning/experiencing driving a simulated racing car, I'm learning how to work around Project Car tyre issues.

It is fake. It's a simulation, which is an approximation of reality. Funny thing is, in reality, real race drivers and real race teams constantly work around their tire/car/track/development/budget/etc issues.

Keena
06-09-2018, 14:32
It can be frustrating but that is not the end of the road. Its the demarcation point between winners and losers.. be open to different points of view and explore the options presented to you. A solution may be just around the corner, at which time all the frustration becomes a memory. Take time away from your career to run some extended testing to truly undestand the problem, then test solutions. Some of them may be radical, sone might just be as easy as sticking softs on, reducing camber and toe and then driving the resulting package within its limits- which may not be pace limited but temp limited! Above all, a Hmmm is better than Wawawa.. ;)

venquessa
06-09-2018, 19:11
So the next race is Hockenhiem. 25*C. Hards were better than Silverstone, but still not practical. I did however get the rear tyres up to 114*C and even go orange and there was still no grip. So if it's temps and those are the actual tyre temps then it's faked based on track temp alone.

Softs got me pole by 2 seconds at 100% AI. However they were bright orange after that lap and I went straight into the wall on turn one as a result on the next lap.

I tried hards in the race at first. They were fine for half a lap and then big, lazy, shopping trolley wheel oversteer until I couldn't drive it anymore. Tyre temps around 100-104.

Put softs on and just couldn't keep them cool. They flash heat in a single corner, particularly the front left, going from ~100 to orange and ~120 in a few seconds.

As the tyre temps change the car balance changes dramatically to the point where I again gave up.

While I did everything I could to keep them cool the AI just reeled me in, when I pushed they got hot and the balance changed depending on what tyre was hot. By the third lap the "freshness" gone in the tyres the inconsistent balance resulted in me slipping around too often and getting punted by the AI.

I don't believe I am overdriving either, I'm not sliding around and can easily adjust my pace when the tyres do get hot and I do understeer/oversteer, but in doing so I just get caught and rammed by the AI. Typically my lap times when the tyres are working are within about 2 tenths of each other.

Going and playing raceroom was like a breath of fresh air.

I know this will pass as I'll be out of the GT4 and hopefully the next cars, GT3 aren't as bad.

venquessa
06-09-2018, 19:17
What pressures are you running when hot ? Out of interest I had a quick go in the GT4 Aston at Silverstone with similar track temps and on Hard tyres it felt nervous for sure but then I only got them up to around 70 -80 degrees so not hot enough as they seem to work best for me around 90 degrees .
On the softs the car felt great with temps around the 80 degree mark which I maintained for around 10 laps before I got bored.

What laptimes are you doing to keep the softs at 80*?

And I believe the tyre pressures where around 1.9bar hot. I was testing with the default loose setup on the softs, default stable on the hards (to get any kind of balance).

Also, this stuff about the colder tyres amplifying the balance. The default stable setup is an understeering as get out, if this is true it should amplify the understeer, not make it oversteer.

I altered the loose setup on the softs to loosen up the diff and stop it pushing/washing out in corners on the power and set the rear wing to 0. I had to adjust the rear antiroll bar one tick soft and move the brake balance to 60/40 to stop some corner entry oversteer on the brakes.

Keena
06-09-2018, 20:34
These might help..
Not mine, just crap Ive collected that's helped me out on some issues that sound similar..

https://www.dropbox.com/s/lz7f7o5dlkk0chw/gt4-cribsheet.pdf?dl=0

https://www.dropbox.com/s/03uzu5uyiwetkyx/PC2%20Tyre%20Chart.png?dl=0

https://www.dropbox.com/s/ewu8iq0a6hojb2j/XSR_SetupGuide.pdf?dl=0

TexasTyme214
06-09-2018, 21:36
I find that in some classes, hard tires do not have the same balance (oversteer vs understeer) as their soft counterparts. If you made a setup that was created around the soft tire, usually the car oversteers when you throw on hards. I've noticed this in GTE, GT1, and LMP1-H. This might be the case in other classes.

hkraft300
07-09-2018, 00:36
The only "balance" difference I've found is only slightly more power oversteer on hard tires, across all the GT and LMP classes. Which is not necessarily a balance issue, more a right foot issue.
In saying that I'm far from the pace Texas drives at.

GT3 hard tires are a stand-out, because they seem different from other classes and is much more reactive to a silly throttle.

So if you can't learn to control it in the GT4 car you're in big trouble in GT3.

If you're spinning on default stable, you're probably pushing too hard.

venquessa
07-09-2018, 06:56
So if you can't learn to control it in the GT4 car you're in big trouble in GT3.


You see I'm fine in the GT3s. I can easily get into the top 20 on the leader boards with the Z4 or R8. I'd be even higher but I don't get along with the track cut penalties. Not that I try and jump across corners, but minor and annoying things like slipping the tail end over an exit curb. At some tracks the are so irritating and the AI cheat them so much I turn them off for single player games.

So I think what is going on here is a bit of expectation. I recall the AM GT4 being a brilliant fun, stable car when I first played the career mode. I have also spend quite a bit of time in the GT3s since. The firs time I was playing with the AM GT4 I was using softs and stable setup with AI at 81%. Now having spent a bit of time in other classes and GT3s with hard tyres I have moved to using the default loose setup and hard tyres, AI at 100%. So now that I have returned to the AM GT4 I'm having issues as I'm expecting stable fun car and getting a finickity sensitive beast of a thing. Frustration is kicking in and I'm still trying to take corners flat to the mat where I shouldn't.

hkraft, I agree with you for the most part, but I'm honestly telling you that the AM GT4 is messed up, it's so unstable even on default stable and softs you have to tippy toe everywhere. Blending out of the throttle in many corners which probably should be flat. I was testing at silverstone with a friends leaderboard setup. It was only when he sent me video that I realised he is lifting in places that don't see to be places you need to lift in. The final turn for example and turn two. These are flat out corners.

Coupled to this the AM GT4 seems to suffer really badly from the "long slow lazy super market trolley wheel spins" the GT cars sometimes do. It's so unforgiving and a little too much throttle in a fast corner and it doesn't do a little catchable slide, it just starts floating at the rear and is virtually unsavable.

I intend to return to the GT3 class tonight to a car I trust and verify I haven't forgotten how to drive entirely, but this AMGT4 non-sense has shaken my confidence.

You can have a laugh at this. I confess by this stage I was angry and just trying to show what a POS this car is. Yes it's over driving, but it's an unstable, unforgiving nightmare. You have to be so delicate with it. I'd become afraid of it to the point where I felt I couldn't even dare to try and retake my line for fear of upsetting it. Time to put the game down and get some sleep.


https://www.youtube.com/watch?v=tm0WwIhaBnc

Happens in the real world to me too, LOL.

https://www.youtube.com/watch?v=nz7Wp5bIQQ4

Cholton82
07-09-2018, 07:17
You see I'm fine in the GT3s. I can easily get into the top 20 on the leader boards with the Z4 or R8. I'd be even higher but I don't get along with the track cut penalties. Not that I try and jump across corners, but minor and annoying things like slipping the tail end over an exit curb. At some tracks the are so irritating and the AI cheat them so much I turn them off for single player games.

So I think what is going on here is a bit of expectation. I recall the AM GT4 being a brilliant fun, stable car when I first played the career mode. I have also spend quite a bit of time in the GT3s since. The firs time I was playing with the AM GT4 I was using softs and stable setup with AI at 81%. Now having spent a bit of time in other classes and GT3s with hard tyres I have moved to using the default loose setup and hard tyres, AI at 100%. So now that I have returned to the AM GT4 I'm having issues as I'm expecting stable fun car and getting a finickity sensitive beast of a thing. Frustration is kicking in and I'm still trying to take corners flat to the mat where I shouldn't.

hkraft, I agree with you for the most part, but I'm honestly telling you that the AM GT4 is messed up, it's so unstable even on default stable and softs you have to tippy toe everywhere. Blending out of the throttle in many corners which probably should be flat. I was testing at silverstone with a friends leaderboard setup. It was only when he sent me video that I realised he is lifting in places that don't see to be places you need to lift in. The final turn for example and turn two. These are flat out corners.

Coupled to this the AM GT4 seems to suffer really badly from the "long slow lazy super market trolley wheel spins" the GT cars sometimes do. It's so unforgiving and a little too much throttle in a fast corner and it doesn't do a little catchable slide, it just starts floating at the rear and is virtually unsavable.

I intend to return to the GT3 class tonight to a car I trust and verify I haven't forgotten how to drive entirely, but this AMGT4 non-sense has shaken my confidence.

You can have a laugh at this. I confess by this stage I was angry and just trying to show what a POS this car is. Yes it's over driving, but it's an unstable, unforgiving nightmare. You have to be so delicate with it. I'd become afraid of it to the point where I felt I couldn't even dare to try and retake my line for fear of upsetting it. Time to put the game down and get some sleep.


https://www.youtube.com/watch?v=tm0WwIhaBnc

Happens in the real world to me too, LOL.

https://www.youtube.com/watch?v=nz7Wp5bIQQ4

Looks like you’ve replaced the rubber tyres for plastic ones , That looks so loose !!! Is that a default setup ?

Invincible
07-09-2018, 07:42
Something isn't right there... I know that the hards can be a bit loose on the GT4's but what happened in the video, shouldn't happen if I'm not mistaken.

venquessa
07-09-2018, 08:33
Something isn't right there... I know that the hards can be a bit loose on the GT4's but what happened in the video, shouldn't happen if I'm not mistaken.

That video was with softs!

Invincible
07-09-2018, 08:53
That video was with softs!

Soft bicycle tires? No, really. This looks odd.
Can you do me a favour and test with a different setup? Prefereably one of the top TT times. Load up TT, add a ghost and nick his setup. See how that works then.

venquessa
07-09-2018, 09:30
Soft bicycle tires? No, really. This looks odd.
Can you do me a favour and test with a different setup? Prefereably one of the top TT times. Load up TT, add a ghost and nick his setup. See how that works then.

It was Cyteless's setup from the leaderboard I was using along with his ghost. He posted a video, though I would need to ask his permission to share it. He is feathering the throttle a lot in the places I am spinning, because they are car is incredible nervous in a lot of places and very unforgiving as the slides are very difficult to catch when they happen.

I'll try this evening with another of the TT ghost setups.

Invincible
07-09-2018, 09:34
It was Cyteless's setup from the leaderboard I was using along with his ghost. He posted a video, though I would need to ask his permission to share it. He is feathering the throttle a lot in the places I am spinning, because they are car is incredible nervous in a lot of places and very unforgiving as the slides are very difficult to catch when they happen.

I'll try this evening with another of the TT ghost setups.

Yes, please. Try one or two other setups. Maybe he really has an extremely twitchy setup.

Bealdor
07-09-2018, 09:35
Looks like a serious setup issue for sure IMO.
Do you know how old that ghost setup is? Maybe one of the patches broke it?

Invincible
07-09-2018, 09:39
Looks like a serious setup issue for sure IMO.
Do you know how old that ghost setup is? Maybe one of the patches broke it?

Ah haven't thought about that. But according to https://pcars.13ms.de/#/laps/315584, his ghost is only 2 days old.

venquessa
07-09-2018, 09:50
Ah haven't thought about that. But according to https://pcars.13ms.de/#/laps/315584, his ghost is only 2 days old.

Yea, he made it while I was chatting to him on Discord about this issue on Wednesday night.

He claims it's stable and planted for him. He does also suggest that the car is horrible and unforgiving.

I'll try a different few setups later but this is generally the way the car has been for me. It even oversteers dramatically with the default stable setup.

However it's an absolute cracker to drive in the rain.

Bealdor
07-09-2018, 09:52
Try loading the setup again and save it under a different name.
Maybe there's a setup loading issue going on here.

Invincible
07-09-2018, 09:59
He claims it's stable and planted for him. He does also suggest that the car is horrible and unforgiving.

I'll try a different few setups later but this is generally the way the car has been for me. It even oversteers dramatically with the default stable setup.

However it's an absolute cracker to drive in the rain.


Try loading the setup again and save it under a different name.
Maybe there's a setup loading issue going on here.

Yeah, as Bealdor said, save it under a different name and then load it again from the new name.
Generally, the Aston GT4 is one of the more stable GT4 cars for me.

SlowBloke
07-09-2018, 10:28
Aston GT4 feels horrible to me on Silverstone oversteer central and thats before you use that crazy setup venquessa mentioned - then it really wants the rears to let go at every given opportunity there.....

Just feels like your on majorly overheated rears that have no grip at all and thats in TT with hards at 90-105 or softs in same range.... Id expect it from the softs but not the hards.

Porsche GT4 much more planted but even then most cars to me at least dont feel like they are planted at all at Silverstone and other smooth FFB tracks like Brno, Indy Road, Imola & Spa.

blinkngone
07-09-2018, 12:03
Try loading the setup again and save it under a different name.
Maybe there's a setup loading issue going on here.

Hey, it is not a loading issue. Cyteless is running no downforce, the rear slow bump is increased to 22000 from 10000 and preload is up to 250 from 80 for starters, pressures are way low as well.

Bealdor
07-09-2018, 12:05
Hey, it is not a loading issue. Cyteless is running no downforce, the rear slow bump is increased to 22000 from 10000 and preload is up to 250 from 80 for starters, pressures are way low as well.

Ouch! So much for "stable and planted". lol

Racing4Life
07-09-2018, 12:08
Generally, the Aston GT4 is one of the more stable GT4 cars for me.
Ähm, imho the Aston GT4 is an oversteering beast, but I love it though. It just needs some adjustments. :)

Aston GT4 feels horrible to me on Silverstone oversteer central
Thats the setup I've created for the Nords. Its pretty neutral and with some minor adjustments it should work at Silverstone too.
259718
259719
259720
259721
259722

rich1e I
07-09-2018, 13:36
That behaviour reminds me of the M3 GT4 which wanted to spin in a similar way at Fuji. Can't remember who started the thread in "The Garage - Setup Talk" section some time ago.
As blink said, increasing rear slow bump that drastically can only lead to oversteer; remove any rear wing and increase preload astronomically and the car should be far from being stable.

Loading setups from other people can help in many cases but it's not granted that they suit your driving style. One reason why I don't like TT is, people make Frankenstein setups that wouldn't even last 3 laps in a race.
I'd say, start everything from scratch. The loose default setup is definitely a good starting point, but soft tyres should be fine in any conditions. If you can get the Group 5 power down easily it should also work with the GT4s. Could also be a hardware issue, I don't know.

I'm going to give it a go tonight in cold conditions and soft tyres and see what happens. I haven't had many races in GT4 but I used to pick the Aston because it was the only car that could challenge the Porsche a little bit and I didn't notice such behaviour.

venquessa
07-09-2018, 13:58
Just remember I start this thread because the car handled absolutely fine in the wet, but threw itself off the road at any opportunity with the default loose set up in the dry.

Using the ghost setup was just a friend trying to help me out.

I'll try again this evening with stable and loose setup and a few other leaderboard set ups.

I know it's fairly stable on softs with the default stable, but still too oversteering for the "stable setup". It's mostly undrivable on the default loose in the dry on any tyres... for me anyway.

cpcdem
07-09-2018, 14:12
Just remember I start this thread because the car handled absolutely fine in the wet, but threw itself off the road at any opportunity with the default loose set up in the dry.

Using the ghost setup was just a friend trying to help me out.

I'll try again this evening with stable and loose setup and a few other leaderboard set ups.

I know it's fairly stable on softs with the default stable, but still too oversteering for the "stable setup". It's mostly undrivable on the default loose in the dry on any tyres... for me anyway.

Undriveable on what, under acceleration or braking? I just tested it on default loose, default hard tires, but also with Traction Control at default, in High mode and it looks fine under acceleration, nothing like in your video. Only in very slow speed corners needs to be careful with the throttle, but high speed are fine full throttle. I suspect your friend was joking with you a little bit by making you use zero downforce :)

Keeping it under control under braking is a problem indeed, you need to make sure to brake in a straight line only, otherwise it gets very tricky. But you can try increasing the engine braking value to max, that should hep a lot with that, too.

About soft tires, why are you suing them, what are the temps? Under normal TT conditions, by the middle of the first lap they overheat, so from then on they do not produce enough grip anymore, so I think it's better to stick with hard tires, unless you're racing/testing in cold conditions.

rich1e I
07-09-2018, 16:55
deleted

Just re-read your opening post lol You just need to keep an eye on track temps. I'd say, below 30°C take soft tyres. Should solve the problem

venquessa
07-09-2018, 18:01
So I believe the ghost setup was a red herring. Yes it's a snappy nightmare with that.

I tried
Default Stable with both soft and hards and managed ok laptimes.
Default loose with both soft and hards and managed ok laptimes.
Neither laps were stellar, it's "paul" on the leaderboard, but it was lap one of the session, I can find another second or two there, I was wide in two corners.

I went to private testing and took "Winter" and 13*C track temps. (Have these people been to England in winter?)
Default stable with softs was fine.
Default stable with hards was a bit of a handful but do able if you overheated the brakes for a lap and then worked on the tyres for a lap.
Defalut loose with softs was doable but it was a handful.
Default loose with hards was very tricky even with force heating them for 2 or 3 laps.

Heres the thing.
As soon as I remove the rear downforce it's back to super market trolley rear wheels. I believe this is the main issue.

Surely that should only really effect high speed corners, but it causes the car to be unstable in 1st gear hair pins at 40mph. Also it's a bit extreme.

So effectively the only negative aspects I can actually raise are that the aero effect is a bit weird and has too much effect at low speed.

That and why the car handles like a dream in the wet with no rear wing but becomes a nightmare in the dry with similar track conditions.

The wet tyres are a different model entirely right?

I had been driving quite a few cars, including GT3 with no rear wing and when the GT4 handled so well in the wet without it in race one of the career mode, I assumed it was also fine without it. So when it handled like a POS in the dry I didn't immediately point my finger there. Cold track + hard tyres + no aero = nightmare.

blinkngone
08-09-2018, 00:15
Hey, maybe you could check out Zeratal's thread on the Aero in PCars2. http://forum.projectcarsgame.com/showthread.php?64780-Pcars-2-Aerodynamic-Model

Also as rich1e said track temps dictate tire choice. As I understand it Silverstone is generally considered a "Downforce" track. If you think it is a no downforce track you are most likely just driving it way too slow. The reason you believe you can drive in the wet and the car "handled so well" in the wet is that you were going much, much slower in the wet and when you went to dry conditions you were suddenly approaching the corners at a much higher speed and the 0 downforce wasn't capable of keeping the car planted at those higher speeds.

Yes the wet tires are a different tire model.

There are low downforce tracks, such as Monza, but Silverstone GP isn't one of them unless you want to just putt slowly around nearly out of control with slick tires on a dry surface. If you take sector 2 at Silverstone with F1 cars for example from Copse to the beginning of sector 3 the corners are taken nearly flat out. They can do this because of the downforce they have(and giant sticky tires). With the Aston you can never generate the downforce of the higher class cars so trying to run 0 in the dry is a waste of effort.

Also take a look at Casey's tire pressure guide in the Sticky section of the garage. Ok, here is the link in case you miss it. http://forum.projectcarsgame.com/showthread.php?57541-Project-CARS-2-Tyre-Pressures

Oh, I don't think your time is all that bad either at this track, if you compare it to all the GT4 cars that have made runs, so I am not knocking your efforts. Just questioning your theories.

venquessa
08-09-2018, 07:29
As per my other post I am fairly sure I am not driving slower in corners in the wet. But I need proof first, so I'll leave it until I get that. It's still open as to whether this is due to the car feeling more controllable and thus confidence inspiring or if there is actually more grip.

Anyway. My challenge now is to beat Cyteless's time :)

Interesting on the tyre pressures for road cars. I run my car at 2.4 bar (COLD). At 2.1 bar there is too much movement and it affects handling. at 2.4bar it's much more go-karty and responsive with less rolling around. The 16" winter tyres I run at closer to 2.6 bar. At 2.1 bar the car is dangerously wallowy and sloppy. Also when going to a track the instructor advised everyone to put the tyres up a few PSI (cold pressure) to prevent the tyres rolling under the rim and damaging the shoulder. Considering stock road low camber. Also, doesn't it also matter the tyre size versus the vehicle corner weight? My car is known to be "under tyred" on 215s (205s winter), so maybe this explains the higher pressure requirement. Space saver wheels are usually inflated to 4.1 bar due to their tiny width. Granted these figures don't automatically apply to producing fast lap times.

Mahjik
08-09-2018, 15:43
Tire differ in construction based on their desired purpose. A street tire is designed to be safe and absorb road noise. To do this, manufacturers use a smaller wheel with a larger tire to create a decent sized tire sidewall (i.e. not low profile tires). The sidewall is a form of a spring. In doing all that, it will have a soft sidewall to make road comfort the priority. However, if you try to drive on a track with those tires, the soft sidewall will bend and cause the tire to roll over the sides in corners. To counter this, you increase pressures but this does have other adverse effects. But, with a street tire, you have to find a happy medium when using them outside of their designed purpose.

Race tires are completely different. They are built with very stiff sidewalls to take cornering loads. They don't care about ride quality with race tires, so the stiff sidewalls will transmit a LOT of road noise to the chassis. With that, you don't require as much pressure. I usually start my real life competition tires around 1.7 bar and go from there. Sometimes I might go up, sometimes down depending on the weather but they will never start cold over 2.0 bar.

hasslemoff
08-09-2018, 15:52
Just remember I start this thread because the car handled absolutely fine in the wet, but threw itself off the road at any opportunity with the default loose set up in the dry.

Using the ghost setup was just a friend trying to help me out.

I'll try again this evening with stable and loose setup and a few other leaderboard set ups.

I know it's fairly stable on softs with the default stable, but still too oversteering for the "stable setup". It's mostly undrivable on the default loose in the dry on any tyres... for me anyway.

I find all GT4's a bit tricky in default set up, especially under braking, i'm the same as they are easier in the wet but no where near as quick as in the dry, the progressive slid in the wet makes it easier to correct, in the dry once the rear goes past a certain angle its hard to catch.

A few tips I use in GT4's in stock set ups is not to be aggressive in down shifts as it unsettles the car under braking, settle the car down with the throttle in fast corners by getting your braking done before you turn in, slow corners are similar but you can get on the power earlier. Been smooth is the best for gt4's.

I did a couple of laps to try the aston at silverstone in TT with the loose setup, hope it helps.


http://youtu.be/-LGcNwjOxrs

Edit: thanks maskmagog for the info how to add a video

Maskmagog
08-09-2018, 16:20
To show videos, use the [VIDEO]-tag and remove the s in https.