LSD ?? What does it do

  • Thread starter Harley45
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Harley45

Harley45

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ScruffybUK
I've read the description in the Game and to be Honest i'm still confused :dunce:

I notice there are lots of Settings to play with and knowing my Luck if I muck around with it i'll make things worse

So Please someone take me through a Idiots Guide in Laymans Terms of the Basics of LSD Tuning and Settings

After that i'll attempt to Tune something and see what happens :ill:
 
if i understand it correctly it manages

1. "starting point" where your engine kicks in
2. how sensitive throttle is
3. how sensitive brakes are

correct me if I'm wrong :P
 
An easy way to understand this is: when a car turns, the inside wheels travel less than the outside wheels. The LSD controls the rotation of these wheels and how much one is allowed to spin independently of the other wheel. Picture a car turning in one direction, if both wheels were spinning at the same rate, the car would tend to go straight rather than turn (understeering). A lower value of LSD means there's a lower threshold before the system makes both sides of the wheels spin at the same rate.

Initial means the value of when the car is coasting, acceleration is when you get on power, and braking is when you're braking.

So for example, if your acceleration value is set to really low, when you're trying to power out of the corner, the wheels are forced to rotate at the same rate, causing your car to go straight rather than turn (understeer).
 
So if what you said is understood by me right...

Lowering the value of the LSD for braking will allow me to make the initial turn into a corner while braking easier?

Its a big pain having to slow down for long sweeping corners that your just too fast for, and braking just makes the car plough.


And then the acceleration one could be used to combat a tail happy FR car too?

Coasting would be the same as braking I assume, just without brakes or throttle?
 
If you click on the link in my siganture or look at the stickied threads at the top of the page you will see some tuning guides.

The second of these covers (among other things) the function of the LSD in detail.


Regards

Scaff
 
Corthalis
An easy way to understand this is: when a car turns, the inside wheels travel less than the outside wheels. The LSD controls the rotation of these wheels and how much one is allowed to spin independently of the other wheel. Picture a car turning in one direction, if both wheels were spinning at the same rate, the car would tend to go straight rather than turn (understeering). A lower value of LSD means there's a lower threshold before the system makes both sides of the wheels spin at the same rate.

Initial means the value of when the car is coasting, acceleration is when you get on power, and braking is when you're braking.

So for example, if your acceleration value is set to really low, when you're trying to power out of the corner, the wheels are forced to rotate at the same rate, causing your car to go straight rather than turn (understeer).
Click to expand...

I think you have it backwards. The higher the value the more firmly the LSD clutch packs engage, making the car harder to turn.
 
Corthalis
So for example, if your acceleration value is set to really low, when you're trying to power out of the corner, the wheels are forced to rotate at the same rate, causing your car to go straight rather than turn (understeer).
Click to expand...

Correct me but I think the less the value the less the LSD is engaged i.e. wheels rotate more independently and therefore more oversteer/wheelspin fro the outer wheel.

The higher the value the more the LSD is "locked" and the more the understeer and less wheelspin.

Also I think braking sensitivity should apply not only to braking forces but decelerating in general which would include lift-off deceleration of the wheels (so you can correct lift-off oversteer or understeer).
 
BTW on average, what do you think is a good initial torque value for maximum effect on accelerating/braking sensitivity???

Should it be in the middle on 30 (say 20 to 40 depending on the car)???
 
Bluez_Freak
BTW on average, what do you think is a good initial torque value for maximum effect on accelerating/braking sensitivity???

Should it be in the middle on 30 (say 20 to 40 depending on the car)???
Click to expand...

I use the following baselines. A lot of people will probably say they're too low, but they work for me. If the car rotates too easily you can always raise the values, but I suggest doing so proportionally i.e. 6/24/8 -> 9/36/12 -> 12/48/16.

FF: 6/12/6 (Actually, I usually don't even bother buying the LSD for FF)
Front engine AWD: F:6/12/6 R:6/24/8
FR: 6/24/8
Mid engine AWD: F:6/12/6 R:9/24/12
MR: 9/24/12
RR: 12/24/16
 
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What should i change if i want more steering on power? My supra understeer like hell on power. I know i need to loosen the diff so the inside rotates more. But i dont understand GT system XD
 
r2nyGT5
it will if your racing on slippery surfaces or tracks with bumps in them (nurburgring)
Click to expand...

So would this be why I keep having my back end pop and hop around while my front has horrible understeer that gets a bunch worse under speed when I am on nurburgring in anything that approaches touring car level?

I have been trying to lessen it with slightly raising and softening my suspension. It got a little better, but still not great. It doesn't help that I suck at driving most of the time, and very well may just be driving too fast. I have to slow down much more then the AI cards do though, or I lose contact in front with the track coming over a hill. I have had more picnics in the grass along the track then I care to admit.
 
Tharain
if i understand it correctly it manages

1. "starting point" where your engine kicks in
2. how sensitive throttle is
3. how sensitive brakes are

correct me if I'm wrong :P
Click to expand...
You're not wrong but your explanation is too short. There's, I think, whole books to write about the LSD in Gran Turismo :)
They are really complicated to understand, especially on 4x4.

- Basically, tune this when your suspension settings are about 75% done.
- Tune your brake ok. The car must be braking the best you can, and when the wheel burnout if you brake violently and very late, the front wheels must burnout before the rear wheels (unless that, you'll have accel problems in the curve)
- Find a gear setting that you love (for precise LSD setups and power distribution, especially for a precise accel setup)
- Find the correct value for the initial torque with your suspension. It depends on your suspension settings and other fixed value like the size of the car and your brake distribution.
Once you're ok with that, put values likes 30/30 in accel and decel.
More accel value = great stability while accelerating in curves but lots of burnouts at the end of the curve.
less accel value = the opposite.

More decel value = stability at the begining of a curve or while decelerating along the curve but the car may understeer badly if set too high.

The "strenght" of the stability that keeps you in the curve is the initial torque. But if set to high, your car will do head to tails a lot under accel/decel presure but decel differential will apply "a lot" then in the curve accel differential will apply "a lot", if you can understand me.

Do +10/-10 on accel if set to high or to low, race, then come back, etc. Then +5/-5, then +2/-2 until you find the correct region. You can go to +1/-1 if you love the car but do +1/-1 tries when you're sure your suspension is completly ok.
Then do the same for decel. +10/-10, +5/-5, +2/-2 and come back when the suspension is finished.

Typically, the higher these values are, the best it is, at the expense of the car stability. You must try your LSD setup under a lots of conditions : long curves (high speed ring ftw) and sharp turns (Rome ftw).

If in the begining of a curve your rear tires loose aderence especially on sharp turns, review your brakes because any LSD setup is useless before that is fixed : you'll head to tail at the end of the sharp turn.

After that, you'll finish your suspenssion and come back on LSD to correct some problem of the car.

etc etc etc. There's a lot of other things to consider while setting up LSD. 4x4 are a nightmare.

Now, there's patterns you could use but it really depend of the car, brakes, suspensions and gearbox.

And btw, sorry for my angrish ! :)
 
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TommyWizard
Lowering the value of the LSD for braking will allow me to make the initial turn into a corner while braking easier?
Click to expand...
Yes, at the expense of the curve stability while still braking in the curve, or using neutral gaz.
It's because of the neutral gaz in the curve that you are forced to put this very high.

There's a lot of thing to do with the suspension, or brake, or even aerodynamics to make a car oversteer so you can put this setting high.
 
cj10
will the lsd help in aceleration?
Click to expand...
Hum, while turning, yes, a lot. That is called autoturn, I guess. For me, this is the Holy Grail when tuning a MR.
Another phenomenom is the slipping you have without abs in straight lines, at the begining of a race for exemple. If set to high, the littlest rocks on the road will lock the LSD and you'll end in the wall.
 
Corthalis
An easy way to understand this is: when a car turns, the inside wheels travel less than the outside wheels. The LSD controls the rotation of these wheels and how much one is allowed to spin independently of the other wheel. Picture a car turning in one direction, if both wheels were spinning at the same rate, the car would tend to go straight rather than turn (understeering). A lower value of LSD means there's a lower threshold before the system makes both sides of the wheels spin at the same rate.

Initial means the value of when the car is coasting, acceleration is when you get on power, and braking is when you're braking.

So for example, if your acceleration value is set to really low, when you're trying to power out of the corner, the wheels are forced to rotate at the same rate, causing your car to go straight rather than turn (understeer).
Click to expand...

This honestly helped so much...Is there anyway to give you reps on this forum?? ;)
 
StangBanger302
This honestly helped so much...Is there anyway to give you reps on this forum?? ;)
Click to expand...

This is why no one can agree.
I've experienced the exact opposite of what that poster had written, but yet you were successful with his techniques. It seems to vary from person to person, which is why it seems we'll never come to an absolute black and white description. I feel LSD works on a sine curve. Where the sweet spot is in the middle, but a randomly defined middle as it varies per car and per person. This is what caused complications with the simple idea that lower = X and higher = Y, because it's completely dependent on where you started on the curve, whether or not, higher or lower is the right answer. I also tend to believe that higher and lower can have the same result, but for the opposite reasoning. You can see why it's so complicated for any single person to explain or back up their theories against anyone else's.
 

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