Radical GT3 tire characteristics

Discussion in 'Bug Reports' started by Stefan_L_01, Jan 7, 2018.

  1. Stefan_L_01

    Stefan_L_01 Registered

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    Hi
    I post this here as bug because I do not know where else:
    The radical gt3 behaves strange concerning S7, S8, S9 compound. There does not seem to be an improvement from S9 over S8 to S7 concerning grip or time at the end. I run several stints for my own but to nail it down I choose the AI to do it. So I took a little testtrack, the "8" of Kenton Fairgrounds, full tank and let them go 20 laps each on a full staturated track (grip), default set else.
    While C7, Bently, AMG gained ~ 0.1 from S9 to S7, the RX showed no benefit at all. Actually the best lap for the RX was better on S9 than on S7 (typically around lap 15 somewhere).

    So I´m sure something is off for the Radical. Whether the tire assignment is somehow off or it is due to other effects, I don´t know, but it certainly does not benefit from S8 or S7 in terms of grip even in a short race. So I´d kindly ask you to look into. This way the radical can not be competetive.
    Thx & Best regards
    Stefan
     
  2. Christos Segkounas

    Christos Segkounas Registered

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    Rad was the first of the pack I test-raced online at Silverstone.
    Yeah, the tires are very different to everything we have had so far, based on the latest tire model updates.
    I was able to get extra lap time in quali-style runs from gradually going softer on the compound, maybe around 0.6 to 0.8 secs per compound though I cannot remember the exact differences.
    I raced the S9 though because softs tended to overheat and made the car hairy to drive through the fast esses in the last 5 or so minutes of the 30min sprint and I had limited time for testing and tuning.
    Without getting into much detail, the softer the compound the more grip you will have at a cost of temperatures.
    This means that over one lap the softest compound will have an advantage but over a race distance the harder ones may actually be quicker, not because of tire wear but because of thermals unless you can find a way around that.
    I did not find the Radical to be different on these new tires vs the rest of the pack.
     
  3. Stefan_L_01

    Stefan_L_01 Registered

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    Maybe it was ok, but it isnt anymore? I tested it right now on a short track, brands hatch short layout. S9/S7 no difference in first 5 laps, especially not in lap 1 which is usually fastest one. Bently -0.8S for the S7 ! Imo there IS something off now.

    Furthermore this track makes a weakness obivious of the radical: The radical is way too instable on the rear, you can not push it into T1 in Brands hatch like the Bently. The Bently is going through the long, slightly bumpy right downhander like on rails, even on brakes, for the radical you have to stiffen the front end a lot to get through (low 44´s), slowing you down compared to other cars anyway. But this is another topic, like the brakes dragging you in every direction. It´s really screwed up in many ways. Sadly, such a nice excotic little car.
     
  4. Christos Segkounas

    Christos Segkounas Registered

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    I'll try to give it a go tonight but I will use Silverstone National instead since I know it better and will take less time to find consistency.
    I still need more testing with these tires anyway.
    The Radical is a handful alright but in the end you do what you have to do and make it work.
    It is fast no doubt and I like to have a different,more challenging alternative for when I get bored.
     
  5. Stefan_L_01

    Stefan_L_01 Registered

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    All right, don´t forget to switch forth and back several times between the tires and keep grip constant. Usually I let 20 AI build up grip with factor x15 so I have a fully saturated track, save / use it and set grip to constant now for your tests.
    About stabilltiy: We drive only abs and traction (gt rules?), not stabillity help
     
  6. Christos Segkounas

    Christos Segkounas Registered

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    I did not switch back and forth because I spent enough time on the hard to not feel I needed to.
    I did Silverstone National on preset_heavy rubber and static realroad, 50 liters of fuel, no driver aids because we don't use them and I don't like them.
    Tire wear on but fuel consumption off.
    I set a laptime of 53.666 with the hard.
    I then switched to the soft and in the end all I managed was to match that time with a 53.671 after repeated efforts.
    There was a difference in feel in that the softer tire felt more pliable but there was no gain of any kind.
    I am quite surprised by this.
    I would love to repeat the exercise with my favorite car, the AMG but I am so fatigued from work it will have to wait til tomorrow.
    I am uploading the two efforts for them to be evaluated by anyone interested and I would be the first to admit that a clean lap would shave off a few tenths from each lap but not tonight from me the way I feel and it would prob be the same for both compounds still.
    My upload speed is slow though so it will take a while.
    I want to test the Merc before I come to my first conclusions.
    As things stand and after this experience I would race the hard with the Rad.
    However seeing as when I did race it(right after release) there was a clear difference in thermal performance between the compounds (and lap time but I will get past that) I would have to test if this is indeed the case still or if the tires are actually identical in all aspects of performance.
    Even though like I said I did feel the soft being more pliable this is not very scientific so I will not insist on that.
     
  7. Christos Segkounas

    Christos Segkounas Registered

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  8. davehenrie

    davehenrie Registered

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    on a previous thread about the NON-gt3 Radical, one person mentioned the car performs better when the front is higher than the rear. I can honestly say I've never heard of that working AND I haven't been able to try it in rF2. But it might be interesting to see if that slightly raised front works with the GT3 car as well.
     
  9. Stefan_L_01

    Stefan_L_01 Registered

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    Christos, so far you confirmed exactly my issue, thx. And I agree the tires are different, they feel different and wear is higher for the S7 / S8 compared to S9.

    Btw: I can still qualify reasonable fast in the Radical, but in the race you get soon eaten alive
     
    Last edited: Jan 11, 2018
  10. Christos Segkounas

    Christos Segkounas Registered

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    Yeah, also tried the Merc tonight.
    Did not have to spend too much time with it before I set a laptime I felt I was happy with.
    So I set a 53.882 with the hard, I expected better because the lap felt real good.
    Then I set an easy 53.462 in the soft.
    Not so much the laptimes but the effort required in the hard to get the lap time vs the soft, I needed a really good lap with the hards to get below 54 and the same was a simple affair with the soft.
    This equates to around 9 tenths difference over a 2 minute lap which is decent.
    So I feel you are on to something.
    The Radical definitely has pace and when I raced the hard in a sprint I got a real good result but that was then and I don't know if they have screwed something up along the way with it.
     
  11. Comante

    Comante Registered

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    Why there should always be a bug or fault when it may very very easily simply need to adjust a bit the setup to maximize a compound over the other, without even considering driving style?
     
  12. Stefan_L_01

    Stefan_L_01 Registered

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    Prove it and dont guess
     
  13. liakjim

    liakjim Registered

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    Tyres are not that different regarding absolute grip.
    You need to remember that tyres different regarding temperature window.
    On a cold day, in a track that don't generate heat like monza, softs will do much better
    Repeat at mugello on a warm day and the softs will over heat making them even the slowest compound.
    Now, radical since it's not like the rest of gt3 cars, might need different approach or set up to highlight the optimum compound.
    Actually, the somewhat different character of the radical, proves in my head that rf2 did a fine job . Same thing happened in kunos' recent tyre model.
    I am just saying that you need thorough testing.
     
  14. Andregee

    Andregee Registered

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    The track temperature doesn´´t matter acutally because undependig of the shown, the simulated track temp ist static.
    The Ai uses the older rFactor1 tyre modell so its not compareable. I am not sure, but i think the AI uses only one tyre modell undepending of selected setup.
     
  15. SPASKIS

    SPASKIS Registered

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    No matter temperature, softer tires are faster but degrade faster. I haven't seen any pole setter using hard tires. Using the ultra soft compound in a demanding track might destroy the tire after one or two laps but should be faster than a harder tire.
     
    marmagas and Christos Segkounas like this.
  16. Stefan_L_01

    Stefan_L_01 Registered

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    There is a difference between the AI enemies and the AI that can drive your car when you are on the track and hit I. For the later one the current tire matters as far as my experience is.
    And dont forget we tested the tires for different cars in very same conditions. If 4 cars behave a way that makes sense and one a way that does not make sense at all, there´s imo no need for discussion (and I will stop answering to guessing and unreflected postings). There´s only a need to validate my issue, but christos did a systematic and neutral job to do so.
     
  17. davehenrie

    davehenrie Registered

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    In GTR2, we proved that pressing I uses a default talent file while pitting and changing to the AI driver uses the talent file associated with the co-driver. I don't know about how rF2 uses talent files.
     
  18. Lazza

    Lazza Registered

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    The AI will only use the new tyre model if you use a special AI mode in devmode. The single player game will always make them use the .tbc file, which is a much simplified version of the tyre model (same as players used in rF1). So it's very dangerous to draw conclusions solely based on AI performance, as a poor mod can have completely different characteristics for those tyres. You can see the proof of this physics change by bringing up the Ctrl-C graph and seeing the CPU use plummet when you enable AI.

    Still, that doesn't mean there isn't an issue (bug or otherwise), just that testing with AI doesn't really prove anything.
     
  19. Christos Segkounas

    Christos Segkounas Registered

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    My thought exactly, you'd expect a softer tire to show an advantage at least over a flying lap.
    I do not claim to be an allien or a robot and that my testing result is final and undisputed.
    But hey, we are investigating and trying to get to the bottom of it.

    Now generally speaking about these tires, they have been a great headache to me.
    I understand that each compound has an operating window and you rely on that aspect to determine which tire to choose for a race.
    So lets say you start a race distance simulation with the soft and determine it overheats after 20 minutes.
    Obviously you want to try the medium next to see if that stays within optimal parameters.
    Where it gets complicated is if you add in driving style.
    By pushing less you may be able to keep the softs singing.
    But by pushing less you start giving up time so what's the point of using a tire that is only marginally quicker in the first place if you are having to give up time to keep it working correctly, you can very well end up going slower with it by babying it.
    Throw in now also setup and you can see where my headache comes from in choosing compound.


    Now on to the Radical, Stefan has reported that there's actually zero performance advantage in the soft tire unlike the rest of the pack and my own testing confirms that.
    So what are the possibilities here.
    1)Our observations/testing are flawed.
    2)There's a bug, someone pressed the wrong button when making/updating the mod.
    3)The geometry/setup of the Radical doesn't compliment the softs, strange as it may seem that even in your first couple of efforts on new tires a softer compound won't give you some extra grip.
    Even stranger because the handling of the car isn't affected by the compounds so it is still cornering just as fine and handling the same.

    I find #3 to be the most likely scenario, that the performance of these tires is so close to each other that for some reason the Radical on the default setup completely fails to extract the extra pace of the soft, for a reason that I am not knowledgeable enough on chassis technology and setup to figure out myself.
    Still I cannot ignore the other two scenarios as being valid but I have a hunch S397 have no idea about what we are reporting here either and are into other stuff right now and won't bother.
    I did inquire on Discord about this and my inquiry got met with the sound of silence followed after a while by Pacman playing in the background:rolleyes:
     
  20. Christos Segkounas

    Christos Segkounas Registered

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    Yeah that makes sense.
    I made a race against the AI at Silverstone and while I seemed to have a slight pace advantage over them, as the track got rubbered-in gradually they became quicker and quicker where I was only able to maintain my laptimes.
    So it seems they are at least capable of making use of extra grip on the track, plus you can visibly see them pushing the car to the limit.
    Again this doesn't mean the AI are the perfect tool for testing but they can be useful.
    And if any of you guys knows how to put the AI on the latest model tire in devmode for a test in the Radical and maybe another one of the GT3 pack it would be interesting.
     

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