General Tuning Guide (Updated 1.09)

Discussion in 'GT6 Tuning' started by DolHaus, Jan 16, 2014.

  1. JTB10000

    JTB10000

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    Sorry accidentally posted it twice.
     
  2. DolHaus

    DolHaus

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    That would be the LSD, the part which transfers the power from the engine to the wheels. Old muscle cars and FF's have what is known as an open differential meaning that power will be transferred to the wheel with the least resistance, in this case the inside front/rear depending on the drivetrain.
    To solve this you need to increase your Accel settings using a Fully Customisable LSD. Before fitting the new part make a note of the stock settings as the custom unit reverts to its own settings when fitted. If you change the numbers back to stock you will have a good starting place to work from. To solve the immediate problem of inside wheel spin you need to increase the Accel number so power is delivered more evenly across both drive wheels, increase by 2 at a time until the you feel like you are getting better drive out of the corners.
    Give the LSD section another read and play around with the settings so you get a feel for what is happening and how you can improve it by making changes.
     
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  3. SDsnakebutt

    SDsnakebutt

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    Im sure @DolHaus will have a good detailed answer for you. But if you don't mind me asking just so there is a little more information given. Is there a particular time you get the single tire spin? turns? accelerating?

    My guess would have to be LSD. Acceleration sensitivity to be specific. I know that the smaller the number the more Inside tires will spin and the Higher the number the more Outside Tire will spin. You keep moving up or down till you can get Both Inside and Outside tires to spin at the same time.

    IDK if this contributes to what you are talking about. @DolHaus Is way more knowledgeable with Tuning than i am so he will probably be able to point you the right way. Thanks for letting me take a stab at ur question tho. Good luck
     
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  4. SDsnakebutt

    SDsnakebutt

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    I hope it was OK that i answered @JTB10000 Question. Its very strange, when i saw his question and than posted my reply i didnt see your post. It now shows your post before mine. If i would have seen you answered his question i wouldn't have posted my post. As you can see from my post i didn't see any Post from you. Sorry about that.

    It is good to see that i was correct tho :) The credit should go to you. Its YOUR guide that has taught me a lot of what i know so Thank you for that.
     
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  5. DolHaus

    DolHaus

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    Not a problem, your answer was indeed correct (as far as I can tell from the question at least).
    Glad you found it useful, it covers the basics but there is still a lot to learn beyond it when turning the theory into practice. I find that once you can identify the cause of a problem then the answer is never far away, just a matter of experimenting to see what solution works best.
     
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  6. adam46

    adam46

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    @DolHaus How would I stop a car from sliding when I lift off?
     
  7. DolHaus

    DolHaus

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    What drivetrain/car is it?
    Could you also please describe the situation a little more in depth (is it happening after braking/throttle).

    It sounds like it might be another LSD related problem where there is too big of a difference between the Initial and either the Accel or Decel figures. My first port of call would be slowly raising the Initial, this will make the drive wheels act more consistently and add general stability but if raised too much then it will make the car difficult to rotate and add understeer. If you raise the Initial you will also need to make small adjustments to the Accel and Decel figures because it influences the way both of them work.
     
  8. adam46

    adam46

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    It's a RUF BTR, and it's off the Accel. I'll try what you've recommended.
     
  9. DolHaus

    DolHaus

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    With the BTR I would also recommend putting some ballast in the front so its less rear heavy and raise the rear ride height to stop it rotating so viscously. Its one of the defining characteristics of an RR drive train, fast turn in but really hard to drive at the limit due to the way the rear swings around like a pendulum unless kept in check.

    If you are new to tuning then I wouldn't recommend any of the RUFs as a project car, they're more than a little tricky to work with and require a quite high degree of skill and experience.
     
  10. LLandmannn

    LLandmannn

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    Might sound like a stupid question , but how could one stop their car jumping about under brakes? I drive a 99 Lancer Evo VI and it jumps around when braking for the 2/3rd last corner after the back straight on Mount Panorama Motor Circuit. Is it my set-up? is it the road surface?
    Please help me!
     
  11. DolHaus

    DolHaus

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    If your car is jumping around it usually means your suspension is too stiff and/or doesn't have enough travel (ride height too low).
    Try adding some ride height first, raise it up 20-40mm and try again to check you are not bottoming out the shocks. If the problem persists start by reducing your damper compression to allow the suspension to react more quickly and suck up the bumps. If the problem is still there by the time you reach 1 then your springs are too stiff and need reducing.
    Bathurst is one of the bumpiest tracks out there, it requires a fairly unique and soft setup. Being that it only has a few high speed corners, the cornering speed losses associated with soft suspension will be minimal and balanced by the increased grip in lower speed sections.
    What tyres are you on? I've never found a road car to feel comfortable on Racing tyres at Bathurst, its too bouncy without proper down force to make the tyres work so you will be constantly snatching at grip.
     
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  12. LLandmannn

    LLandmannn

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    Thanks a lot DolHaus I'll try that tomorrow :bowdown::bowdown::bowdown:
    I usually am driving on sports soft or racing soft (if the host allows it). I'm usually ok with the amount of grip I get apart from the crest at the top of the mountain, I need to brake early or risk sliding sideways into the next corner :lol:
     
  13. DolHaus

    DolHaus

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    No problem, hope it helps.
    When running Racing softs on road cars it needs to be as stiff as possible to work the tyres, this presents problems on bumpy circuits because the car will be bouncing around all the time and grip level will drop and spike constantly due to the car skipping over bumps.
    Road cars have a fair amount of flex in the body and chassis which makes them not ideal for the conditions that racing tyres require, the suspension could be made of solid steel with no give at all but the body shell and chassis will continue to wobble around on top causing unexpected weight shifts and other stresses. I'd strongly advise that you fit the rigidity upgrade at GT Auto if you are planning on running race tyres, helps get rid of some of the issues but it will never solve it completely. Unlike GT5, race tyres just don't work with some road cars, the platform can't match the performance.

    Just to clarify, you are talking about the braking section after The Chase (long fast kinked straight turning hard left at the end)?
    Is it locking up and sliding at the rear under hard braking or actually bouncing? If its locking up and sliding it could be a brake balance issue or an LSD decel problem.
    Are you noticing the front end diving into the ground? If so that could mean your front springs are bottoming out under braking and you will need to increase the front spring rate and/or damper compression. (this is why you need stiffness with racing tyres, they put huge load on during braking and cornering. The tyre wants to stop but the body wants to keep going)
     
  14. SCClockDr

    SCClockDr Premium

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    I use this very place to tune my braking balance as a first step. I do a hot lap from the garage and save the "Best Lap" replay. (Needs to be a valid lap.) I then fire up the Data Logger, load that replay, and maneuver to that section and look at the wheel speeds vs vehicle speed. {I use tab 2 with Speed, Left Front Wheel Speed, Right Front, Left Rear, Right Rear} I shoot for ~ 20-25Km/h difference front & 15-20 Km/h difference rear. I then scan the corners for accel. & decel. places while turning to look @ left/right wheel speed differences if any. My goal here is ~1Km/h outside wheel faster than inside. (Most FR cars come in around 22 accel. & 14 decel., I use a torque of 10 mostly.)
     
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  15. LLandmannn

    LLandmannn

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    I got the rigidity upgrade and it helped a fair bit , cheers for that
    Yeah the chase is where it happens really bad , raised the height and lowered the damper compression and it seems to help. The brakes aren't locking up or sliding and its not literally jumping up and down it just kind of turns by itself when I'm braking hard. When i try to correct it slightly it would turn sharper than I wanted it to and this sometimes leads to my back wheels hitting the grass and the car ploughs into the sand. It seems to turn right when braking for the chase more often than left , I don't know if this means anything or it could be the angle that the track is on or something.
    Thanks for your help so far
     
  16. DolHaus

    DolHaus

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    What are your current LSD settings and brake balance? Sounds like you need to raise the LSD Decel numbers to stabilise and balance the wheels under braking and prevent it rotating. The other thing could be the brake balance slowing one end of the car down faster than the other causing rotation.
     
  17. Thorin Cain

    Thorin Cain Premium

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    You do learn something new every day!:p

    I just had a good read through this section and lesson received.:tup:

    I never really gave this one much of a going over before as I though I had a decent grasp of the LSD functions from the other sources I've read. But the Initial tuning section showed me a thing or two, I had never known that the Initial functioned in this way exactly. I knew the basics open=more oversteer, locked= more understeer, but until I read this I never really understood the effect it actually has.

    Thanks again for opening my eyes a little further @DolHaus!:cheers:

    Edit: Doh! Forgot the reason I was here. I'm wondering how you find it best to approach the LSD for 4WDs?
     
    Last edited: Jun 17, 2014
  18. DolHaus

    DolHaus

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    No worries, they're remarkably simple once you understand what it does. All it basically is is a way of setting the speed differential between your drive wheels, this can be hugely influential on a cars handling characteristics particularly on RWD setups.
     
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  19. Thorin Cain

    Thorin Cain Premium

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    I'm pretty sure it's just what I'd been looking for, I just didn't get that there was the relationship between the Accel. and Braking through the Initial.

    So just to make sure I have got this right. The initial setting is what I'd use to limit how drastic the difference is between Acceleration and Braking whilst using just throttle control through a section of corners(i.e S-bends at Suzuka.)?
     
  20. DolHaus

    DolHaus

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    Initial (pre-load) is the most dominant setting, anything below this value will not register
    Accel and Decel are separate from each other so changing one will not effect the other
    The closer accel/decel are to the Initial setting, the smoother the transition between phases will be (ie. lifting off the throttle while cornering - if the numbers are close then the car will be stable and continue turning at the roughly same angle, if the initial is way lower then the rear will start rotating faster potentially causing instability)

    Basically if theres a big difference between initial and accel/decel then you get quite a jerky transition between the phases which can upset the balance. Imagine hitting a very small pothole, not big enough to impact the car but enough to upset it on corner entry or exit
     
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  21. Thorin Cain

    Thorin Cain Premium

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    Thanks again my good man! It's all crystal clear now:tup:
     
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  22. DolHaus

    DolHaus

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    No worries :cheers:
    The other thing to remember is that if you are using lower figures on Accel then you will end up losing acceleration because of the way energy always looks for the easiest route.
    What happens is when you corner the weight is transferred away from the inside rear wheel, this makes it easier to rotate and you end up with a one tyre fire when giving it some throttle. The power is basically going to the easiest wheel to spin and not where you need it. Tighten up the diff and you force it to be more equally distributed because it can't rotate the inside wheel as fast as it wants
     
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  23. Thorin Cain

    Thorin Cain Premium

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    I really appreciate your help. I find it so much easier to put everything together when I know exactly what the tunable parts are actually doing, as opposed to the usual "This causes oversteer,That causes understeer." descriptions I have seen elsewhere.

    Thanks again for your time and help with this. :cheers: And for producing this guide, it really is a great help and a huge asset to the community!:tup:
     
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  24. DolHaus

    DolHaus

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    You are most welcome.
    Yeah I know what you mean, I wrote this for beginners who might not understand the ins and outs of every tuning option and tried to include an overview of what the parts are doing. I could go on for days about how every part works and how it might affect other parts but it would get too complicated for those just looking to make their car a bit better. I'm more than happy to explain the more complex parts if asked, I enjoy it frankly, gives me something to focus my mind on.
    Its a little bit tricky to give firm answers about what will or will not happen when changing various settings as the tuning model of GT6 is so complex and it really does vary from car to car. I can usually look at a setup and see roughly how it will perform but sometimes there will be ones that defy the trend for reasons that are beyond me. These are all little nuances that need learning, that's what I love about the game.
    We all learn through shared knowledge on forums like these, I'm not overly competitive so I don't see a need to withhold tuning tricks from other users. If me helping another driver with tuning makes them faster on the track then so be it, just means that I have to step up my game next time.
     
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  25. Thorin Cain

    Thorin Cain Premium

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    I could not agree more! When I first discovered your guide that's what I liked about it. It didn't get too technical and your bullet points in each section were superb for me to use as a kind of diagnostic tool if I was having issues. As I'm not all that experienced, for me it was perfect for that. I had no problems understanding the other guides in the forum and I learned a great deal from them but sometimes you just need to get a quick recap of some of the finer points and I felt most of the other guides, although very well done, were just a bit too heavy for that purpose. And for me even though some of them contained great information they failed to cover the way things actually work and more importantly their relationships with other settings and for me that is critical to get a proper understanding.

    I like the technical aspects more than the cause and effect approach, I just feel that in order to make the right change at the right time it helps to know how and why the moving parts do what they do and how best to utilise their functions. And in that sense I have really learned quite a lot from your kind self in the past month or so through our various discussions here and there.

    I really do appreciate the time and effort you (And others.) put in to assist us lesser experienced tuners to get to grips with things and it is due to people like yourselves, that this is such a great community to be part of.
     
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  26. JTB10000

    JTB10000

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    Last question then I'm done being a noob: how do I adject the brake balance so that the wheels don't lock up so early while braking?
     
    Last edited: Jun 19, 2014
  27. DolHaus

    DolHaus

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    Are you using ABS?
    What phase of braking is the lock-up happening?
    Is it locking all 4 wheels (skids straight on with no steering possible) or just the rear (back end comes round under hard braking while steering)?
     
  28. JTB10000

    JTB10000

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    Yes, I meant without abs (forgot to add that part). I just want to know, in general, how to tune for the brake balance since I am going to start driving without abs. Thank you in advance.
     
    Last edited: Jun 19, 2014
  29. DolHaus

    DolHaus

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    I don't really use ABS 0 personally but when I've played with it I found you generally use much lower figures.
    If you were using a slight rear bias with ABS, lets say 5/6, you might want to use 2/3 without.
    @Ridox2JZGTE might be able to give you a better explanation?
     
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  30. Ridox2JZGTE

    Ridox2JZGTE

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    I'll quote these 2 great posts about no ABS driving, it's from GT5, but should give good starting point in GT6 ( GT6 has much better braking physics and better braking input, so on most cars, higher brake balance can be used )

    Generally, with steering wheel/pedal input, higher at the front is the norm, but if you have pedal mods or can trail brake effectively, add more rear brake will beneficial to add more rotation under braking, beware though, too high might lock the rear early or cause over rotation under heavy braking.
     
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