PDA

View Full Version : Something is up with tire selection and grip level



sigurd
26-09-2017, 02:38
So it was pointed out in another thread that the formula c car was having seemingly excessive lift off oversteer. Someone later found that the car behaved more normal and with higher grip levels using the wet tire leading one to believe the grip levels were backwards.

This got me wondering if other cars possibly suffer from this.

I just finished a long test session with the m6 gt3 at Daytona road course (dry) with warm track temperature. I have more confidence, grip, feel of under/oversteer steer and feel of abs lock with the wet tire. All of these things equal to a better average lap time (1.2sec) average faster lap but more importantly a better feel.

I also noticed that the wet tire doesn't even try to overheat on a dry warm track...

Someone else give this a shot and tell me if I'm crazy or something.

Kinna39
26-09-2017, 03:05
yeah absolutely something's off. It seems on some cars it's fine but others are all messed up. I was playing Formula Rookie with the auto tire selection in perfect conditions and it would take 4-5 laps to warm up to half decent levels and still suffered lift off oversteer. When I manually changed to the slick tire it was perfect. Tires would heat up to optimal in about a lap and you could actually control it.

On some other cars though that fix doesnt seem to work and might need more playing around to figure it out.

For now I'm trying to stick to cars that are manageable with stock set-up. Porsche GT3 is a great drive.

Jussi Karjalainen
26-09-2017, 03:26
Tested here on the PC retail build (so that possible test build differences won't come through), though I happened to be on the McLaren 650S GT3 rather than the M6 GT3.

Daytona road course in clear conditions with the default date (21/05/2017) and I was seeing bad overheating on the wet tyres whenever I was in the twisty section, easily reaching 100+ C (the rain tyres have their peak performance at very low temps, around 70 C or so), though the long banked sections do help keep it under control in the long run. As soon as the tyres got hot I had trouble with braking and steering, felt like I had very mushy and non-grippy tyres on the front end of the car.

With the hard slicks I was a comfortable 2.5-3 seconds faster per lap, temps well under control, setup was identical except for the tyres.

A couple of things that could lead to this come to mind:

What was the date and weather you set? Being as exact as possible, preferably checking and including the ambient and track temperatures from the session will help us make sure we're doing the same kinds of tests.

Were you in a practice type session that starts on cold tyres? Since the wets warm up quicker and work at lower temps I could see them being capable of being quicker over a couple of laps right out of the pits, but everything in my testing has them way slower than the slicks when they're in their operating temperatures.

And could be that this is some sort of bug that affects the PS4, which we then will need to hunt down.

If you can provide more information, especially the ambient and track temperatures you're seeing, it would be much appreciated.

Jussi Karjalainen
26-09-2017, 03:28
yeah absolutely something's off. It seems on some cars it's fine but others are all messed up. I was playing Formula Rookie with the auto tire selection in perfect conditions and it would take 4-5 laps to warm up to half decent levels and still suffered lift off oversteer. When I manually changed to the slick tire it was perfect. Tires would heat up to optimal in about a lap and you could actually control it.

On some other cars though that fix doesnt seem to work and might need more playing around to figure it out.

For now I'm trying to stick to cars that are manageable with stock set-up. Porsche GT3 is a great drive.Formula Rookie has lift oversteer by design, that's not something that will go away easily. Brake on the straights, then balance the car around the corner with the throttle. If you need it to dive in more, lift a bit. Especially on a wheel the default setup has a fully open differential, like the real cars have, so lift-oversteer is somewhat a part of the experience. EDIT: Note, to help the controllers we added the option to put in some decel locking on the car (30 degrees = most decel locking, 90 degrees = no decel locking), which stabilizes somewhat on corner entry. You can use it even with a wheel, though for maximum realism leave it off.

The tyres on the Formula Rookie and the Formula C are running a bit cool (though they do also operate at lower temps than some other tyres), we are investigating closer.

Jussi Karjalainen
26-09-2017, 03:56
Tested on Xbox One as well, on gamepad, this time using the M6 GT3, this time I was 4 seconds quicker on the slicks, they just felt way nicer everywhere on the track when up to temperature.

If you guys can replicate we'd love to nail this down if indeed there is an issue. The more information you can give (car, track, date, weather, ambient/track temperatures are the most pertinent ones) the better for quickly solving any potential issues! It's still possible it's for example a PS4 only thing.

sigurd
26-09-2017, 04:04
Tested here on the PC retail build (so that possible test build differences won't come through), though I happened to be on the McLaren 650S GT3 rather than the M6 GT3.

Daytona road course in clear conditions with the default date (21/05/2017) and I was seeing bad overheating on the wet tyres whenever I was in the twisty section, easily reaching 100+ C (the rain tyres have their peak performance at very low temps, around 70 C or so), though the long banked sections do help keep it under control in the long run. As soon as the tyres got hot I had trouble with braking and steering, felt like I had very mushy and non-grippy tyres on the front end of the car.

With the hard slicks I was a comfortable 2.5-3 seconds faster per lap, temps well under control, setup was identical except for the tyres.

A couple of things that could lead to this come to mind:

What was the date and weather you set? Being as exact as possible, preferably checking and including the ambient and track temperatures from the session will help us make sure we're doing the same kinds of tests.

Were you in a practice type session that starts on cold tyres? Since the wets warm up quicker and work at lower temps I could see them being capable of being quicker over a couple of laps right out of the pits, but everything in my testing has them way slower than the slicks when they're in their operating temperatures.

And could be that this is some sort of bug that affects the PS4, which we then will need to hunt down.

If you can provide more information, especially the ambient and track temperatures you're seeing, it would be much appreciated.


Daltona road course
21/5/17
19:00
87* ambient
98* track
Clear weather

M6 gt3
Stock setup
Wet tires

8 Laps into session hottest I could get tires even overdriving them was 213*F

Jussi Karjalainen
26-09-2017, 04:11
Thanks for the info!

That's already a good 20-30 C/35-55 F past their peak, they're overheating quite well. Roughly equal to getting the Hard slicks to 120 C/250 F, maybe more.

sigurd
26-09-2017, 04:35
So after even more testing my lap time disparity has closed to basically the same give or take after about 8 laps. Just not seeing the big difference you are seeing in hard slicks times.

Also it's hard to describe but I still feel like I can attack harder with less chance of lift off oversteer with the wets even if it's not really translating into a much better lap time I feel it's safer?

If this is all a big hunk of nothing I'm sorry I really don't want to spread misinformation. Just feels like something is kinda wacky

Were you 2.5 to 3 seconds faster on the hard slicks after a few laps or are we talking 25 laps in? I am still running roughly the same lap times after 8-10 laps on hard slicks vs wets even if they are overheating.

Kinna39
26-09-2017, 04:51
I'll try some testing of my own tonight.

From what I can remember of when I found the manual change to slicks worked, I was at Sakito and the auto-selection was just not getting to temp and I couldnt hold the back end at all - was about 4-6 seconds off the AI when I got a clean lap in. I pitted, selected slicks, went back out and instantly noticed that it was a hell of a lot grippier and also got the tires into the green within 3 quarters of a lap. I was then able to match times with the AI and qualified 2nd.

Civic
26-09-2017, 11:52
The issue is track dependant. For example if you select Oulton Park your Slicks in the Formula R and some other cars will not get up to temperature but if you take the Formula R to Bahrain the Slick tyres get up to temperature fine and have more grip than the Wet tyres. When the Slicks refuse to get up to temp the Wet tyres have more grip. When the Slicks get up to temperature they have more grip than the Wet tyres.

This is on PS4.

Civic
26-09-2017, 11:54
So just to be clear I don't think this is a grip issue with the tyres. I think this is a temperature issue with certain combinations where certain tyres on some cars will not heat up properly at some tracks.

sigurd
26-09-2017, 13:18
So just to be clear I don't think this is a grip issue with the tyres. I think this is a temperature issue with certain combinations where certain tyres on some cars will not heat up properly at some tracks.

I am beginning to agree with you. I also think that the Daytona road course is track that will make this more apparent because the tires have such a long time to cool during the oval section.

I will have to play around with it some more myself. Last night it was pretty clear to me that up to 10 laps the wet and dry tires were giving me similar lap times but I had much less chance for lift off oversteer using the wets. On Daytona the two main places for this are coming off the oval into turn one where the ass end gets really light and also the entrance to the bus stop.

The wets after 8-10 laps were technically overheating as previously mentioned but the grip loss wasn't really degrading as bad as I would expect. On the flip side I also noticed that on the hard slicks I was barely able to keep them at a decent temp even several laps in.