Custom wheels give all 4 tyres the same width.... changes grip and balance

Discussion in 'Gran Turismo 6' started by Vagabond, Dec 18, 2013.

  1. Vagabond

    Vagabond Moderator

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    Now confirmed on several cars and by multiple sources, we have discovered that fitting custom wheels gives your 4 wheels/tyres of the same width. So in the case of cars that have wider rear tyres on stock rims, you lose rear grip and the whole balance of the car is ruined.

    This is an announcement of fact, not a debate. If you choose not to believe it for whatever bizarre reason, please keep it to yourself. The thread is here to be informative so I'd rather keep pointless debate out of it if you don't mind. :tup:

    See here:

    [​IMG]

    This is definitely an example of a cut corner in production and one I hope gets un-cut pretty soon. I realise its only a cosmetic sacrifice to leave the wheels stock on most cars but what's the point in being to 'upgrade' your wheels if it makes the car undriveable when you do.
     
    Last edited: Jan 4, 2014
  2. Mubble

    Mubble

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    There's no evidence that not having a staggered set up with custom wheels ruins the balance - as you put it. It's pretty much just graphical. I wouldn't worry about it.
     
  3. Vagabond

    Vagabond Moderator

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    Actually the effect is actual not just graphical. As an example, I was 3 seconds slower around Deep Forest in a stock F40 with custom rims. Myself and @Stotty tested several cars and each had the same result.

    Believe me, I would not make a thread about it if I wasn't 100% sure... I don't make threads.
     
  4. Lawndart

    Lawndart

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    Ironically, most production cars that are staggered, tend to get "squared off" for completion. Ie 350z...

    Check the ford GT for what should be obvious if it gets squared off.
     
  5. Lasercats2

    Lasercats2

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    Guess i will be holding off on completely customizing my cars than. Thanks for the heads up
     
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  6. Slirb

    Slirb

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    A very simple test to confirm this is to take a stock Cizeta V16 to High Speed Ring and then fit aftermarket rims. The long banked corner goes from understeer to oversteer
     
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  7. Brainhulk

    Brainhulk

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    I wouldnt say ruin the balance. Some people prefer more front end grip and people should use it as a tool to do so. If you balance it with adding more rear downforce, you have yourself a faster car.

    Good to know though.
     
    Last edited: Dec 18, 2013
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  8. Coenraad

    Coenraad

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    Does this go for every rim or only when you increase size?
     
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  9. Normalaatsra

    Normalaatsra

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    Will avoiding increasing the rim size prevent this? EDIT: Tree'd

    This has potential disaster for Huayra users, the rear wheels are much larger than the front set.

    I wonder if my Z31 constantly oversteers due to the custom rims.
     
  10. HuskyGT

    HuskyGT

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    Wow. I just hope this is a joke.

    Does it affect ALL cars or just the mentioned? At least the Cizeta, the Huayra and F40 are cars that I never planned on changing the wheels on.
     
  11. oppositelock

    oppositelock

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    Except this doesn't add front grip, it reduces rear grip, which isn't the same thing. And it only effects cars with staggered tires, which usually have larger rear tires specifically because they need more rear grip. Finally, adding a drag inducing wing to counter act this loss of rear grip sounds like a formula for going slower, not faster.

    I've tested a few cars so far and I think the OP is correct. After beating my head against the wall tuning my Stratos, I went back to stock wheels and the car drives noticeably better. Bizarre.
     
    Last edited: Dec 19, 2013
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  12. Brainhulk

    Brainhulk

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    PD would not reduce the width of the rear tire. add a rear wing and increase rear downforce. And post your results
     
  13. oppositelock

    oppositelock

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    It's your theory. You're supposed to test it, not me.
     
  14. Brainhulk

    Brainhulk

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    Im not the one complaining. Your name is opposite lock, thats what normal racers use when they have oversteer...
     
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  15. Slirb

    Slirb

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    I just tested the Cizeta V16 at High Speed Ring with my wheel(DFGT). Bone stock I managed a 1:13.116. With just the aftermarket rims I was able to hit 1:16.063. While there is more time to be found in both (I was a full second quicker with stock rims one lap till I messed up), it would take a greater driver than me to knock 3 seconds off the aftermarket time. With stock rims the car wants to kick the rear end out in slow corners, but is surprisingly stable at high speeds and actually understeers at speed. The aftermarket rim version requires very minute wheel adjustments and wants to kick the rear out at any speed. Lift-off oversteer is present in both, but with the aftermarket wheels it is much more pronounced.
     
  16. Daddybird

    Daddybird

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    This has nothing to do with complaining but a staggering production fault by PD. And if you do have a theory that would change or better it you need to come up with proof, not let someone else prove your theory.
     
    Last edited: Dec 18, 2013
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  17. Johnnypenso

    Johnnypenso Premium

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    Very interesting results thanks @Vagabond :tup::tup:
     
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  18. Chrunch Houston

    Chrunch Houston Premium

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    Why don't they just give us a skid pad? (grumble, don't pay us nuthen, grumble dont give us no tools. grumble grumble)
     
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  19. Slirb

    Slirb

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    Stock Size:
    [​IMG]
    +1 Inch:
    [​IMG]
    +2 Inches:
    [​IMG]
    The size looks the same for each custom tire, but I cannot say for sure if the handling is different for each size.
     
    Last edited: Dec 18, 2013
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  20. HuskyGT

    HuskyGT

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    That's just horrible... Why would PD do this? My enthusiasm for this game is decreasing day by day... I just hope this only happens in certain cars. At least the Cizeta is one car that I wouldn't change the wheels of.
     
  21. SavageEvil

    SavageEvil

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    Relax it does not look intentional, it just seems that someone goofed and when you install custom rims they do not just copy the width from the original wheels and instead copy the width of one front wheel for all four corners. Now time to draw PD's attention to this because honestly we should be able to choose the width of tires on many car models. Taller rims also increase unsprung weight, but taller front wheels can help with turn in on rear drive cars, in fact many cars run on taller front wheels than rear, S7 is one of them.
    PD got to work with Yokohama Tire and I was expecting to see more indepth tire selection and more tuning choices for tires and wheels. Widths and size were the first things that sprung to mind, but we get size and no more options and a bug for increasing size which gives you four front wheels and a lot less contact patch. It's funny because I remember someone talking about PD not utilizing contact patch in GT6 but clearly they do else no one would have noticed the craptastic handling after getting 4 skinny tires on cars that come with fat rubber rears.

    Is there a centralized thread that has a single list with problems in GT6 that need immediate attention? I don't see on stickied on the main GT6 forum. How many problems have we come across that actually mess up game play from a tuning standpoint?
     
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  22. Aloha62_2

    Aloha62_2

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    Well if it's good if you are into drifting!

    Silver linings and all that jazz.
     
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  23. Rdp616

    Rdp616

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    Custom wheels did the same thing on some cars in GT5 also. This is nothing new.
     
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  24. Aloha62_2

    Aloha62_2

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    I know over the past few years a few of the Lemans LMP's have run wider front tyres then rears, could this be used to give such cars wider rear tyres?
     
  25. nasanu

    nasanu (Banned)

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    Can we confirm that once you reinstall the stock tyres that the widths reset?
     
    Last edited: Dec 18, 2013
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  26. alonsof1fan91

    alonsof1fan91

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    Not just Huayra, the Enzo has 245 front and 345 rear... I would like to either increase the front or decrease the rear size to solve this cars handling issues, but 245 on the rear is nuts xD

    PD, pls fix this!
     
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  27. Stephanos82

    Stephanos82

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    Excellent find!! Good job! Now the hard part --> get PD's attention to fix this! Maybe someone who speaks japanese can tweet Kaz???
     
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  28. millross

    millross

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    Cheers for the info, Chris!
    One thing - is the effect FULLY reversed if you revert back to the original wheels? I've added custom rims to a few cars but haven't noticed the difference as I suspect the tyre widths were coincidentally the same, but interested to know if you can "undo" it properly, or whether it's that bad a bug that it's irreversible.
     
  29. dipdor

    dipdor

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    hi all, I have a suped up supra that I popped some flashy rims on, just for fun and it definitely changed the handling! lnstantly noticable on my first drive, made the car much less fun to drive. easily remedied by ditching the wheels and never visiting that section again!
     
  30. Stotty

    Stotty Premium

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    Yes, car reverts to normal when you re-fit the stock rims.

    Original testing and highlighting of my suspicions is here...

    https://www.gtplanet.net/forum/threads/rufs-and-tire-physics.293069/

    Post #16
     
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