Throttle liftoff oversteer, how to correct with LSD?

  • Thread starter Thread starter Merquise
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Merquise

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I have the RUF BTR '86, loooove the car.
Found out that increasing rear camber a lot helps against the very loose rear end. It's driveable, when it breaks out it does so slowly not like a cat clawing your eyes out..

However, I still have the problem that when I lift off from the throttle too fast, the rear breaks out. I *think* that can be solved by fiddling with the LSD.. but I have no clue what to do ..

Anyone have a tip? Raise every number or lower it?
 
IT being raise (initial torque) will cause it to lock and unlock easier and with less snap.

You probably wont be able to get rid of it too much though, porsches are just like that.
 
Poppins
IT being raise (initial torque) will cause it to lock and unlock easier and with less snap.

You probably wont be able to get rid of it too much though, porsches are just like that.
Click to expand...

I just wanna get rid of the feeling that there is 100 liters of water sloshing around in a bathtub on my rear axle.....
I'd be happy if it would feel like 50 liters of water ;)
 
Merquise
I just wanna get rid of the feeling that there is 100 liters of water sloshing around in a bathtub on my rear axle.....
I'd be happy if it would feel like 50 liters of water ;)
Click to expand...

What's what you get with the engine at the back.
 
Usually INcreasing the DEacceleration is the fix for this, but... as Frieght mentioned, this car's issue is extreme rear weight, not LSD.

The best tip, is to master the art of trail breaking and overlapping the gas and brake pedals.
 
Lol increasing the deceleration value causes more lock up under braking so no, that definately wont help.
 
Adrenaline
Usually INcreasing the DEacceleration is the fix for this, but... as Frieght mentioned, this car's issue is extreme rear weight, not LSD.

The best tip, is to master the art of trail breaking and overlapping the gas and brake pedals.
Click to expand...

I know how to do that, problem is I can't turn my wheel fast enough (it's a 900° wheel). In a past long ago I broke my wrist (a few times actually) with gymnastics on the Uneven Bars (actually it wasn't the bars it was making contact with the floor ;) ) so I can;t turn really fast.

If GT5 would have G25 support I could set it to 270°, maybe then I would be fast enough..



I also found a 'new' problem..
Monza, the first fast corner after start/finish, my front wheels have enough grip to make the turn... but the rear of my car starts breaking.. slowly...... more and more and when I counter it with opposite lock I fly off to the left.
Spectacular to see if you drive behind me, but it's not good for my laptimes when I crash into the wall.

This is what happends.
 
If extreme rear weight is the problem, how about counteracting it with a ballast with a front-bias?
It would probably reduce the performance and all but it would make it easier to drive allowing for more consistent lap times.
 
Easiest way to explain the LSD is like this...

Accel setting- Adjust as needed for corner exit issues. Increase if car understeers, decrease if it oversteers with throttle ON.

Decel setting- Adjust as needed for corner entry issues. Decrease if you get understeer on corner entry when throttle is not being applied or under heavy braking. Increase if you are having instability on corner entry.

So from what it sounds like, trying increasing your decel setting. Change your brake balance to the front and lower the rear 1 or 2 clicks. Also increasing the initial torque setting a couple clicks will help. Based on the limited information you have given us not much more can be said.
 
Guys, I may be completely wrong by saying this, but I was noticing something like this at Laguna last night in my Pug.

If you're using manual transmission, then you may be shifting down while turning.
I think that this is caused by the sudden increase in power and loss in torque that it causes the back end to kick out.

To fix this, try to make sure that you shift all the way down to the gear you want to be in before you start to turn.

Again, that may be completely wrong and untrue, but I fixed it without actually tuning, so...
 
Poppins
Lol increasing the deceleration value causes more lock up under braking so no, that definately wont help.
Click to expand...

Right, because in your world 'more lock = loose condition' right?
In my world, the more the rear end is locked, the more control you have, and the more understeer you get.
Since his issue is that the car want's to spin out when he lets off the gas, the logical thing to do, is add understeer, by increasing the amount of lock in the LSD, which as I stated, is by increasing the LSD DeAccel.

You can offer him your advice, I'll offer him mine.
The arguing of alternate theories does not belong here.
 
Adrenaline
Right, because in your world 'more lock = loose condition' right?
In my world, the more the rear end is locked, the more control you have, and the more understeer you get.
Since his issue is that the car want's to spin out when he lets off the gas, the logical thing to do, is add understeer, by increasing the amount of lock in the LSD, which as I stated, is by increasing the LSD DeAccel.

You can offer him your advice, I'll offer him mine.
The arguing of alternate theories does not belong here.
Click to expand...

Interesting when i increase lock the car becomes more stable as well. We must live in the same world.
 
Good advice people, I'm gonna try the tips you've given me :)

But.. how about that second problem?
Monza, no chicanes. After start/finish straight, that first corner to the right. The very fast corner.

My BTR'86 steers (Racing Soft tires), halfway the corner the rear begins losing grip, at that point all is lost nothing helps.
I tried fitting the BTR with a rear spoiler (on top of the standard spoiler, looks rediculous...), maxed the downforce rear but still.
At ~250 km/h the rear starts breaking and nothing can be done against it.

Any way to counter that sort of thing?
 
Raise your deceleration value and initial torque 10 to 20and your acceleration 5 to 10. This is how I fixed the same issue with my super velouce
 

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