Make a 4X4 Oversteer (LSD SETTINGS?) ???

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Mayonaiske
Most 4X4 cars turn realy stiff/understeer/Always wanting to drive back streight.
How Should This be fixed ?

The 10Front 90Rear settings yes.
But what about LSD settings ?
What makes a 4x4 Maximum Oversteer ? I am asking couse i dont know.
Here's what i have been doing :)

Most extreme:
Front / Rear
5 / 5 Initial... For lowest torque needed to set your locks ?
5 / 60 Accel. For open in front and Locked rear ?
60 / 5 Deaccel. Locked front and open rear ?

So if u:
accelerate your frontwheels got freedom And your rear are locked and twiching for losing grip in bends ?
Deaccelerate the front locks and rear opens so your back gets forced to outside of the bend ?
Or do i need to feel realy stupid ?
:dunce:
I KNOW NOTHING
(Edit: Should this be in tuning forum? sorry.)
 
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Front | Rear
Initial | 5 | 60
Acceleration | 15 | 60
Decceleration | 5 | 60
 
Most 4X4 cars turn realy stiff/understeer/Always wanting to drive back streight.
How Should This be fixed ?

The 10Front 90Rear settings yes.
But what about LSD settings ?
What makes a 4x4 Maximum Oversteer ? I am asking couse i dont know.
Here's what i have been doing :)

Most extreme:
Front / Rear
5 / 5 Initial... For lowest torque needed to set your locks ?
5 / 60 Accel. For open in front and Locked rear ?
60 / 5 Deaccel. Locked front and open rear ?

So if u:
accelerate your frontwheels got freedom And your rear are locked and twiching for losing grip in bends ?
Deaccelerate the front locks and rear opens so your back gets forced to outside of the bend ?
Or do i need to feel realy stupid ?
:dunce:
I KNOW NOTHING
(Edit: Should this be in tuning forum? sorry.)

High lock will always induce understeer.

Optimal settings to make a AWD car oversteer as much as possible seems to be 10/90 for the diff and 5/5/5 for the front LSD.
For the rear LSD it depends on the car, although I would recommend you start at 10/25/15 and lower the last 2 values until the car oversteers to your liking.

Off course the suspension too might need some tweaking, but thats an other thing.
 
High lock will always induce understeer.

Optimal settings to make a AWD car oversteer as much as possible seems to be 10/90 for the diff and 5/5/5 for the front LSD.
For the rear LSD it depends on the car, although I would recommend you start at 10/25/15 and lower the last 2 values until the car oversteers to your liking.

Off course the suspension too might need some tweaking, but thats an other thing.

I KNOW NOTHING :D

Thank you i go try it tonight.

More replies are welcome :)


Whe need an option to set 0Front and 100Rear (Delete the Front wheel drive :p )
FF should never been invented.

Front wheels should to the turning not pulling the car forward . thats what rear wheels are for ...
 
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I KNOW NOTHING :D

Thank you i go try it tonight.

More replies are welcome :)


Whe need an option to set 0Front and 100Rear (Delete the Front wheel drive :p )
FF should never been invented.

Front wheels should to the turning not pulling the car forward . thats what rear wheels are for ...

You have obviously never driven a car in real life before.
 
I tried your settings.
First on a Subaru Impreza Sedan WRX STI Ver. VI '99 (i found it in my standard list with 0 miles)
Sport Soft tyres -> Sport Exhaust , Sport Filter , Sport katalist , Gearbox , Diff Splitter And Custom Diff.
1200+ Kg , 355HP (486pp)

Standard (10/40/20 front and back) : Pretty good ...
37Kaz... settings : not good :)
Canedian... settings : Made it all Very good :)
my old setup... CRAP :D

Then i tested CANEDIAN... setup on my R8 on race softs And it drives much better.
Thank you !!! now i got the basic setting for "GOOD 4x4"

5/10
5/25 -> = Good
5/15

OFFTOPIC SORRY:
You have obviously never driven a car in real life before.

Thanks to belgium car tax system (powerfull engine is superHIGH tax).
I never drove anything real powerfull.

My car history.

-I learned to drive with dads Mercedes E200 D.
-My moms old square Opel Corsa 1.2s (for about a month)
-BMW 318D compact (my first car. Rearwheeldive ofcourse but only 90hp)
Nothing twitching and pulling when accelerating in an angle.
-Honda civic EP4 (diesel) My worst car ever. (crashed it with no regrets losing it)
-Opel Astra (the model most people buy GSI's to tune. mine was dull diesel)
a quick secondhand cheap buy for going to work after civic crash.
-Audi A6 (Avant for the famely i started. 1.9 TDI 130hp. i Love it)

Next in line will be Dodge ram hemi (350hp V8 Kickass) :p (need 6 seats ;) and dont wanna end up with a vw bus or S-Max or french crap car something.)
since its Taxed as a "Work load vehicle" its cheaper than my old 90hp bmw in taxes. and most here run on LPI so its same cost as a diesel that uses 8liters on 100km. (dodge calculated at 20liters lpg)

I drove a VW touareg V6 (smallest engine for it) for 1 day
A Nissan 100NX (2.0 Dual carb) for a week. Fun times :)
For work maybe 2 times a month: A land rover defender , 2011 Mini D , Vw jetta , mercedes Vito , opel vivaro And a citroen's "mercedes sprinter" big one (dont care wats its name :p).

For that SLOW cars it dont realy mater if you got FF , 4x4 or FR
But the BMW was nice to drive , the steering wheel never moves an inch when accelerating ... its comfort.
AND FUN ON SMALL ROUNDABOUTS IN THE RAIN :D (rain needed to make a drift only 90hp ...)
(the 100NX was on ff limit with its power/weigt ratio. Always keep it from skidding when taking off fast :p with the narrow standard wheels )

I know in other country's these cars are not normal for a car lover but here they are if u are a 9to5 workman ...

The dodge ram ill Buy a 4x2 only ...
FF cant go much higher than 200hp (heavyer cars 240?). Whitout having to hold back to much on accelerating from a standstill.
FF is WRONG !!! (4X4 is good for heavy supercars to keep power on track or for offroad stuff) FR is the way to go for fun !

What about you Redline? Your from USA ? Most US cars (with a bit of power) are FR ...
Like us europeans somewatt more entended to love Japanese and/or USA cars (+our own Good brands BMW and stuff)
Do you more entend to love Japanese and european cars ? just out of quriosity :)
 
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I think the stock LSD should be fine with a 20/80 - 30/70 split. In MT its easy to control understeer unless your getting major understeer. Mess around with your toe a little bit, see if that helps.
 
5/5/5 front with only 10% power minimizes the front diff's impact on the car's performance, whether it be positive or negative. Having said that, I have never rendered the front differential so useless in any final 4WD car tune because when it's dealt with properly, it actually improves the car's performance (over 5/5/5 and 10/90).

As for the necessity for FF, it comes down to safety and packaging more than anything else. Having the power go to the wheels that also control the steering is only logical. However, when you put a FF car on the track and try to boost performance a considerable amount (as most do in driving games), you run into problems stemming from weight transfer, the main one being understeer. I don't drive my own personal FF car on race tracks, I drive it on roads, and those roads ice over at times and since that particular issue isn't the norm, it's nice to know the car will still stay butter-side-up.

I think the stock LSD should be fine with a 20/80 - 30/70 split. In MT its easy to control understeer unless your getting major understeer. Mess around with your toe a little bit, see if that helps.

Toe isn't everything. I would even go so far as to say that the toe setting is less important than the spring rate and anti-roll, of course with dampers adjusted to suit. Higher spring rates and anti-roll bars in the rear minimize weight transfer during acceleration and cornering and thus increase the grip of the front end in a FF or 4WD car.
 
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Stock- 45-55 or 40-60 F-R power distribution, then just slide the car using the brake and mash the throttle to pull out of the slide.
 
FF cant go much higher than 200hp (heavyer cars 240?). Whitout having to hold back to much on accelerating from a standstill.

Torque steer is more an issue of suspension design and packaging limitations than an inherent limitation in the FWD concept. Also, as the name implies, the phenomenon you are referencing has to do with the amount of torque applied; the engine's peak horsepower is not necessarily related (especially on highly-tuned naturally aspirated engines with low torque but high horsepower due to high RPM designs).

In any case, ~300 ft-lbs of torque through the front wheels seems to be the practical point we've reached lately in terms of it being reasonably practical to go to the expense of designing a suspension and steering geometry that doesn't massively torque-steer. The biggest problem is that a suspension design with large negative scrub radius (necessary to prevent torque steer) is difficult to engineer from a practical standpoint and also makes the steering feel much "heavier" at low speeds which is undesireable in cars used as basic transportation.

Still, this is less a limitation inherent to FWD qua FWD, but more a result of pragmatic compromises in suspension design that represent engineering tradeoffs that must occur in mass-market vehicles.

FF is WRONG !!

From what perspective?

In terms of efficiency, FF (or RR) absolutely destroys the "traditional" FR layout. By eliminating the need for a long driveshaft, the total drivetrain losses for a FF (or RR) layout are lower than losses for a similar FR car. By eliminating the driveshaft (and, as a result, the driveshaft tunnel) a car using FF (or RR) provides much greater interior volume than a similar FR car. In terms of assembling the car at the factory, FF (or RR) has the benefit of greater ease of powertrain installation as well. So FF (or RR) is more efficient in terms of space, manufacturing, and friction.

In terms of safety on public roads, FF is superior to FR (and soundly trounces RR). Yes, in the hands of a competent driver, FR is just fine in the winter, but most people on the roads are not competent drivers. And when some idiot in a FWD car panics, he's simply going to understeer. This means the car will lose control in a very predictable manner and generally also remain front-first allowing the most efficient use of the vehicle's safety systems. Put an idiot in a RWD car and you get a lot more spinning out. There's a reason that manufacturers intentionally tune even RWD cars (if destined for on-road use) for understeer.

In terms of low-speed traction and directional control in snow, FF again trounces FR. As above, yes, a competent driver can manage with FR, but FF is unquestionably better-suited for inclement weather and this is especially so when one considers the relatively low speeds seen by street cars. FR's disadvantage is made even worse by the fact that the majority of FR vehicles are still front-heavy with significantly less than half their weight on the rear drive wheels. This can make establishing traction in snow much easier in FF cars (and also RR) where the engine's weight over the drive wheels is beneficial and vehicle speeds are quite low.

Yes, FR (and MR) has better "feel" than FF. Yes, FF suffers at both the dragstrip and on a road course. Yes, a good driver will prefer FR over FF in dry conditions where the car is being pushed hard.

The problem is that none of those matter in everyday use. In fact, in terms of average use (0-75 miles per hour, driven in all kinds of weather, driven by people with wildly divergent skill levels, driven in societies where fuel efficiency and space efficiency are critical aspects of automotive design), it's FR that's "wrong." FF is far more "right" for any sort of use on public roads.

In real-world driving on public roads, there are many, many reasons why a practical individual would rate FF as superior to other 2WD options. FF allows greater passenger space for the same exterior dimensions. FF is easier to put together on an assembly line. FF behaves more predictably in the hands of the average commuting motorist.

Racing is an entirely different question, of course. A FF racecar would be at a disadvantage in a track environment if all else was equal. But the fact that something is sub-optimal in a single area does not mean that it's "wrong" in other areas, no matter how mundane those other areas may be.
 
Yeah cosworth boys stripping off the FF part of their Ford's do it to make the car drive worse ???

If i find a time machine i go back in time and Delete FF from history ;)
Then everyone learned to drive FR (MR/RR)
And with electronics there is no more danger for dummies on Rearwheeldrive then they are on ff.
People that live in Snow area's drive 4x4 with 0/100 and a button changes it to 50/50 :p (lets call it the SnowTrax system :p )

The world should be a better place...

Imagine every honda Rearwheeldrive :)
 
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