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Poll : Do you use induced understeer?

no
131
yes
59
#1 - JeffR
Induced understeer to counter lift throttle oversteer?
First a video showing extreme usage, just to demonstrate the technique, not how it should be used, from an old version of LFS:

http://jeffareid.net/lfs/lx6.wmv

Note this is a technique for rear wheel drive cars.

Preventive usage: in real life racing, some cars get better lap times when setup to be a bit oversteery in faster turns or under lift throttle. To stabilize these cars in the situations where the cars are prone to oversteer, the drivers will steer inwards a bit past maximum grip so if the rear end get loose, the front end will washout transitioning the car into a 4 wheel drift instead of spinning. Few real race cars need this, but I have corresponded via email with a few drivers that do this.

Lift throttle oversteer recovery usage: if a car looses the rear end due to engine braking, normal counter-steering can only be used if the oversteer is caught before it gets too far, and the brakes can't be used while counter-steering (this will make the oversteer worse). If the oversteer is more severe, or braking is needed, then steering inwards hard will usually wash out the front end, allowing the car to recover, slowing it down more, and allowing usage of the brakes. If nothing else, at least you go off track facing forwards.

High speed flat out turns (such as ovals): keeping the fronts tires turned inwards just a bit beyond optimal can stabilize a car under full throttle in a high speed turn on a non-downforce car. (Most downforce cars have relatively more rear downforce to prevent high speed oversteer, since the snap oversteer in a high speed, high g turn in such cars is virtually unrecoverable).

Normal countersteering: Note for corner exit under throttle, normal counsteering is used. Easing off the throttle here will increase the grip on the rear tires.

How many racing games are there where induced understeer works? The ones I know of are Grand Prix Legends, LFS with certain cars, and GTR2 with most cars. In the case of Grand Prix Legends, you could enter turns faster, and modulate the throttle and steering inputs to slow the car down while turning inwards for the corner apex, an alternative to trail braking that made it easier control speed and attitude during a turn. In the case of Grand Prix Legends, cornering feels more like a controlled drift because of the high slip angles involved with the racing tires on those 1967 Formula 1 cars.

The poll is asking how any here use induced understeer?
I never knew this was possible in LFS
From what I read that technique is used frequently by iRacing and GPL players.
Doesn't make much sense to me, and I'm not that sure I could turn the wheel that fast. Plus I hate understeer above anything to start with.

Probably don't, at least intentionally.


Nice retro video btw.
#5 - SamH
I've used it loads in LFS, in the LX6.

The same technique actually saved my ass in real life. I came off a roundabout near Triere. It'd just rained really hard after a really hot dry spell, and I think the road had that slippery rubbery film you get. I was in an Astra Estate and the back-end just came straight around. I just drove straight out of it by deliberately and instinctively inducing understeer by turning in instead of counter-steering. I thanked LFS and the LX6 at the time.

It sounds silly to compare an Astra Estate with an LX6, but I think the weight distribution is probably very similar. Lots of weight at the front, very little at the back. Perhaps if I'd had a heavy load in the rear at the time, the car wouldn't have acted so LX6-ish. Especially since the Astra is FWD and the LX6 is RWD. Power was off at the time though.
Quote from SamH :It sounds silly to compare an Astra Estate with an LX6, but I think the weight distribution is probably very similar. Lots of weight at the front, very little at the back.

Interesting theory:

LX6 Weight dist:
48.0 F 52.0 R
#7 - SamH
Hmm.. doesn't work that way then does it? LOL! All that engine and it's heavier at the rear?
#8 - senn
Quote from SamH :Hmm.. doesn't work that way then does it? LOL! All that engine and it's heavier at the rear?

Gearbox, rear axle, more bodywork, interior, all towards the rear. It's only a 1.9L inline six, not an overly large engine..

from what i can gather on the video, this essentially looks like using tyres scrubbing on the ground to reduce speed? if the back end steps out, why not lift a little (i'm talking Front engined cars here, with RWD, Mid rear and Rear rear are a different kettle of fish) counter, and if you have an LSD, attempt to power it thru (i'm talking race use only here)

I'm struggling to see the advantage of inputting too much steering, as, at least in that video, it seems to wash off way more speed that i would think necessary?

I might be wrong tho, if anyone can explain whats happening better that would be good..
#9 - bbman
Quote from SamH :Hmm.. doesn't work that way then does it? LOL! All that engine and it's heavier at the rear?

Just radiator, lights and front suspension in the front, the engine about bang on in the middle, with the gearbox, drivetrain and driver adding to the rear already...
Quote from SamH :Hmm.. doesn't work that way then does it? LOL! All that engine and it's heavier at the rear?

The engine of LX6 is placed _very_ far back behind the front axle. I think the actual weight distribution of it is close to 45/55 with driver, even more rear biased with fuel added.
Quote from SamH :Hmm.. doesn't work that way then does it? LOL! All that engine and it's heavier at the rear?

FR cars tend to have a weight distributions approaching 50/50, the LX even more so because of the very rearward cabin
#12 - SamH
Quote from senn :from what i can gather on the video, this essentially looks like using tyres scrubbing on the ground to reduce speed?

[..]

I might be wrong tho, if anyone can explain whats happening better that would be good..

The idea is to exceed slip angle and so break traction on the front wheels.
#13 - senn
thats what i mean, it seems like a technique that is putting a car from a 2 wheel loss of traction into a 4 wheel loss of traction...it breaks with most of what i've been taught about driving a car (i'm not saying it's incorrect, just i haven't encountered it before)

Does it have any advantages? Any Disadvantages? Where is it best used as opposed to the normal correction techniques that are taught?
#14 - SamH
Quote from NightShift :FR cars tend to have a weight distributions approaching 50/50, the LX even more so because of the very rearward cabin

I wonder if the Astra with 2 people and travel luggage in the back would balance the car

I've always assumed the Astra would need more than just my ex wife's chopped-up remains and accompanying chainsaw to make the car balanced.
#15 - SamH
Quote from senn :thats what i mean, it seems like a technique that is putting a car from a 2 wheel loss of traction into a 4 wheel loss of traction...it breaks with most of what i've been taught about driving a car (i'm not saying it's incorrect, just i haven't encountered it before)

Does it have any advantages? Any Disadvantages? Where is it best used as opposed to the normal correction techniques that are taught?

It is essentially inducing 4-wheel slide. I'd always (apparently wrongly) assumed that the additional engine weight at the front, and its accompanying momentum, would effectively invert the whole effect and introduce more skid at the front than the rear, thus resulting in the understeer. I'm thinking I'm going to have to re-visit that idea though.

[edit] I'm not sure that it's an accepted "technique". I found it's just faster to induce the understeer by turning the wheel another 200 degrees than turn a wheel all of 500 degrees in countersteer. When it's needed, it's needed very quickly and what makes it most effective is how quickly it can be deliberately brought on.
I countersteer, since nothing else feels natural. It seems to work for me, so I have no reason to change methods. Interesting though.
Quote from SamH :I wonder if the Astra with 2 people and travel luggage in the back would balance the car

You could try playing a bit with added mass on the FXO, to make it estate you should add around 100 kilos(*) on the back, but the CoG would still a bit too low vs the real thing.

Quote from SamH :I've always assumed the Astra would need more than just my ex wife's chopped-up remains and accompanying chainsaw to make the car balanced.

Well if your ex also has a friend, you could throw his own remains in the back as well

(*) I suppose, haven't checked the specs.
#18 - senn
GENERALLY speaking FWD's will push understeer most of the time, i managed to get a corolla with modified suspension to snap oversteer, but i entered the corner with a fair idea that it would snap over on me....ie too quick. I think you'd have to be pretty unlucky (or have a dynamic load in the rear of the car, large fluid filled container, or unrestrained heavy load etc) to get it to oversteer...

RWD's (FR) if you set them up correctly shouldn't oversteer so much that you can't correct in time, unless you are pushing way past the limits of the car anyway, in which case tough titties :P (thats IMHO)

THAT SAID - i do run my G25 at 270deg in LFS, to get a quicker countersteer, as i find using the full angle of the cars to be too slow to respond. Maybe that just says something about my driving technique tho..
PS, this is the bit I was talkin about:

Quote :
As for physics, I am still a bit undecided still with iracing. Just by looking at the skippie I have a feeling that there is still something wrong with the physics, i can't believe that the way you need to drive the skippie to go fast is any much more realistic than LFS', for example. Mainly it is about the GPL style steering into the corner to counter the effects of oversteer. The more oversteer the more you need to steer "inwards". So far it has totally killed the skippie for me and tbh. I'm a bit afraid that the prototype car and the lotus will be the same. The same steering style works to some degree with the solstice as well.

Personally I haven't read or seen a one single book or dvd about driving a car fast that would encourage you to steer more into the corner when the rear starts stepping out. I know that quick steering will make the car understeer as stabbing the brakes can do but in iracing you need very minimal steering into the corner and the car balances itself into small slide. What I'd expect is to see the car keep rotating more and more when you steer more - as with more steering the car's rotation speed would increase and you'd spin - not stabilize the car.

http://www.lfsforum.net/showthread.php?p=925317#post925317
in fact iRacing requires this technique somewhen but in LFS its nuts.
#21 - SamH
but all this skidding is slow, and isn't getting you to the finish line any faster...

wouldn't it just be better not to oversteer at all?
#23 - senn
of course, sliding of any kind is going to cost you time...but i'm still trying to grapple with how washing off speed by scrubbing the fronts is helping you...maybe its only if the track is cambered a certain way etc?? yeah got me stumped..
#24 - SamH
Quote from bunder9999 :but all this skidding is slow, and isn't getting you to the finish line any faster...

wouldn't it just be better not to oversteer at all?

With the LXs it's not so easy. The cars are very lively and aren't so fond of raw traction.

The turn-in understeer is apparently very pronounced in iR. In LFS, I've found it to be very advantageous in situations like the one in the video posted.. a near-hairpin corner. If you countersteer on SO City T1, you're far more likely to be in the right-hand barrier, since on that corner one of the things you need to do is scrub some speed on entry to make the corner at all. Countersteering works best in wide sweeping corners, of course. This method in LFS does achieve more of a reduction in linear speed than countersteering, and if used effectively can allow you a greater corner entry speed, getting ahead of other drivers.

IMO, the effect in LFS is pretty damn good. Even though it's instinctive for most/all of us to countersteer, there are situations where this controlled understeer explosion serves a purpose.
Quote from baSh0r :in fact iRacing requires this technique somewhen but in LFS its nuts.

iRacing heavily relys on it to be fast, and once you get the hang of it, it becomes quite natural feeling.

FGED GREDG RDFGDR GSFDG