Tuning to reduce lift-off oversteer

Discussion in 'Gran Turismo PSP' started by peterjford, Nov 1, 2009.

  1. canieaturchikn

    canieaturchikn

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    i don't think we are talking about drag racing here
     
  2. Rotary Junkie

    Rotary Junkie Premium

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    You are amazing me.

    Very, VERY much so.


    I give up seeing as you're simply looking straight past what I'm saying and going on and on about what the springs are doing. It's a matter of the suspension travel itself, not the bloody springs.

    Edit:

    No, really?

    It was an example.


    I give up. Just... *sigh*
     
  3. SiNiST3R

    SiNiST3R (Banned)

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    How many times do I have to tell you, your talking about the RATE the weight is transferred not the amount, but stiffening the springs on paper shouldn't do what you suggest, however maybe this specific car it helps due to maybe a stock setting that is simply too soft (Balance remember), Ill give you that.
     
  4. Rotary Junkie

    Rotary Junkie Premium

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    How many times do I have to tell you I'm not talking about the rate weight is transferred at?

    That would apply IF I was another one of the idiots saying stiffer front springs will help (which coincidentally they will, but only by shocking the fronts into sliding as well thereby reducing cornering limits). I'm not. I'm saying that stiffening the rears has the side effect of reducing rear expansion/droop travel and thereby reduces forward weight transfer by way of keeping the CoG from moving upward and forward.
     
  5. SiNiST3R

    SiNiST3R (Banned)

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    What your not getting, is that travel is only AFTER the weight has gone into motion, and the stiff springs in the rear and rear springs travel rate are incapable of impacting the AMOUNT of weight being transferred AFTER the weight has gone into motion............................ It can only impact the rate that the weight is transferred.....

    What your FEELING when tuning is a difference in transfer rate, but your incapable of distinguishing the difference. So I keep telling you TRANSFER RATE, NOT AMOUNT, but you don't listen......

    Your amazing Me!
     
    Last edited: Nov 2, 2009
  6. Rotary Junkie

    Rotary Junkie Premium

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    Ugh.

    The travel is indeed only happening after the weight is already in motion, however, the longer the travel lasts, the more weight is allowed to transfer...
     
  7. canieaturchikn

    canieaturchikn

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    ok so on any vehicle, lets say a bicycle. lets say one that has front springs and dampers but NO rear spring or damper(example of your logic). if you brake just as hard as a another bicycle that has springs and dampers all around but the fronts are stiffer than the rear going the same speed...which one will have exhibit more forward weight transfer?
     
  8. Rotary Junkie

    Rotary Junkie Premium

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    The same considering bikes are generally light enough to lift the rear tire completely off the ground ;)
     
  9. canieaturchikn

    canieaturchikn

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    if you are calling me an idiot because i questioned your logic then you are simply not listening. i took your logic into consideration before i said anything to offend you and i still don't think i have.
     
  10. SiNiST3R

    SiNiST3R (Banned)

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    Now your tossing crap at the wall, its too late AFTER the fact, once the weight is in motion that's it. Physics.
     
  11. Rotary Junkie

    Rotary Junkie Premium

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    I called you an idiot? Where?

    When?

    Your bicycle example was indeed trash because to achieve optimum braking on a bike you generally will lift the rear tire. Hell, motorbikes as well.
     
  12. Rotary Junkie

    Rotary Junkie Premium

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    Ugh. Really?

    Really? Your understanding of physics is apparently fatally flawed if you can't see this.

    If the car stays level under braking then it will transfer x amount of its weight. If the suspension is allowed to let the rear expand then AFTER THE WEIGHT BEGINS TO TRANSFER the center of gravity will begin to move and allow further weight to transfer.

    Edit: Crap, double post. Merge please mods?
     
  13. canieaturchikn

    canieaturchikn

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    right here.

    and my example was not trash bc i said the second bike had stiffer front springs and dampers.
     
  14. Rotary Junkie

    Rotary Junkie Premium

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    Mehhhhh.

    Didn't realize you were amongst that brigade at first. And I now don't care, seeing as it rather obviously wasn't pointed directly at you.
     
  15. canieaturchikn

    canieaturchikn

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    then i don't care as well. but since you have sparked a tinkering inside me i will try out your logic in GT and see what happens.
     
  16. SiNiST3R

    SiNiST3R (Banned)

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    It your lack of understanding that surprises me

    When something is set in motion what does it take to stop it?

    Do you think the springs being Stiff achieves this?

    No it doesn't, Physics
     
  17. SiNiST3R

    SiNiST3R (Banned)

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    This is a very common error for tuning newbs, usually to gaming tuners.

    Only the ride height can impact the Amount of weight being transferred, its been argued by newbs over and over and over and over again, but in the end Physics doesn't change,and neither does the amount of weight transferred after the fact.
     
  18. Rotary Junkie

    Rotary Junkie Premium

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    Ach-hmm? Excuse me?

    I could've sworn I've been doing GT4 tuning for over 2 years now. I also thought I did fairly well in pretty much every tuning challenge. I guess that was all an illusion and I'm a noob. :rolleyes:
     
  19. canieaturchikn

    canieaturchikn

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    okay i'm leaving b4 this thread goes to trash.
     
  20. SiNiST3R

    SiNiST3R (Banned)

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    http://phors.locost7.info/phors01.htm

    Tuning in GT4 for 2 years doesn't qualify you for much.
     
  21. Rotary Junkie

    Rotary Junkie Premium

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    Did you actually read that or just use it as copypasta?

     
  22. SiNiST3R

    SiNiST3R (Banned)

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    YOU are the one who needs to read it, this is stuff you should already know. With your arguments being so wrong, then having the nerve to insult My understanding, HA.

    Don't get confused, it seams you may be already. Mixing up something that is important (like I said) but secondary (like rate of transfer ;) ) Stop tossing Crap at the wall...

    Get to learning Boy! Read up!
     
    Last edited: Nov 2, 2009
  23. Rotary Junkie

    Rotary Junkie Premium

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    Seriously? You're now calling me "boy"?

    Seriously? Just because I don't agree with you?

    If you can't see how the center of gravity moving around affects weight transfer then I can't help you. And because of that, I'm going to sleep. Think of something better than insults and idiocy to use on me by morning (actually you've got roughly 3 hours).
     
  24. SiNiST3R

    SiNiST3R (Banned)

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    You need to realize is the Weight is always rotating around the CG, and that NEVER changes. What you keep talking about would only manipulating said weight, not increasing or decrease it.

    Your Thick, It does have an effect (I never said it didn't) However it doesn't INCREASE the amount of weight being transferred because its after the fact, Boy.

    Why do you think that travel is left OUT of the equation, and not accounted for ANYWHERE when applying the formula to the car traveling around the track. SURELY if what you say had any weight to it (did you see what I did right there, "weight" to it, get it, get it?) it should be taken into account shouldn't it?

    Now get to bed, its past your bed time.
     
    Last edited: Nov 2, 2009
  25. Blitz187

    Blitz187 Premium

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    I saw in earlier posts people referring to +0.20 rear toe in GTPSP as toe-out... For GT PSP this is incorrect....

    Positive toe in GT PSP = toe-in

    Negative toe in GT PSP = toe-out.....

    So all cars come stock with +0.20 toe-in... not toe-out....
     
    Last edited: Nov 2, 2009
  26. Rotary Junkie

    Rotary Junkie Premium

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    *coughs*

    Simplicity. Obviously. It's an entry-level attempt at letting people understand the physics behind it rather than an exact model.

    I'm done here. You know what they say, don't you? Never argue with idiots, they'll only drag you down to their level. Seems I made that mistake last night.

    Edit: Aaand Blitz, the toe is most definitely toe in, thanks for the first sensible post in a page and a half. Although, it's 0.20", not "20".
     
  27. Blitz187

    Blitz187 Premium

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    LOL... thanks, I'm going to fix that little typo, just for the sake of being precise ;)
     
  28. CaptCalvin

    CaptCalvin

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    Wow this all happened in one night? Take a scale that uses springs and take an electronic scale that doesn't use springs. Put objects with the same amount of weight on each. Which appears to have more displacement? Which gets a heavier reading? Now apply that newly learned knowledge to the concept of weight transfer in cars :) Of course one can argue that the CG is above the wheels so if the car angles more to the front under lift-off, more weight would be transferred to the front, but the affects of this is minimal when talking about weight transfer under speed changes.
     
    Last edited: Nov 2, 2009
  29. SiNiST3R

    SiNiST3R (Banned)

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    Forget it, his argument was trashed when I explained the sus travel was after the W/T has been set in motion. Anything after that fact unless its a equally powerful force acting against the weight, doesn't change the amount in motion. Any SLIGHT variation of ride height due to the W/T doesn't matter. The weight is already rotating around the CG of the car.

    Now hes trying to save face, by playing a victim, and calling people idiots at the same time.

    Boy, don't make me take off my belt!
     
  30. Greycap

    Greycap Premium

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    There's nothing for him to save. Believe it or not, he's right. You're not. As it is, a stiffer spring compresses less when force is applied on it, no? That's why the logic of stiff front springs sounds good.

    Oh well, your own quotes to the rescue. They're the easiest way to explain this.

    First you admit that lowering the centre of gravity reduces the amount of weight transferred - which is exactly what it does. But then you turn the coat entirely and say:

    When in fact RJ is indeed lowering the CoG during the weight transfer during braking by, yes, stiffening the rear springs. While the stiffer spring will compress less with force X than a softer one it will also expand less, keeping the rear lower which leads to the CoG staying lower and thus the amount of weight transferred being reduced when compared to the softer spring.

    With stiff front springs and soft rear springs the pivot point for the weight transfer would be somewhere behind the front wheels and slightly above the front axle level. The front would squat slightly and the rear would go up, raising the CoG, putting some more weight on the front and noticably lightening the rear wheels. With soft front and stiff rear springs the pivot point would be somewhere in front of the rear axle and slightly below the rear axle level. The front would squat severely and the rear would go up a bit, lowering the CoG, compressing the front suspension and lightening the rear a bit. You can guess which version produces more overall grip.

    RJ knows fully well what he's doing when it comes to GT tuning. And this is coming from one of his "mortal enemies", not one of his best pat-my-back buddies.