Difference between Understeer & Oversteer

[kashutu]

I was wondering that if anyone can explain what is the difference between
Understeer & Over steer. Thanx

[RS-Studios]

yeah I would like to know also> But i think I have a rough idea!

[topcat]

understeer:Condition where the rear wheels of a car have more grip than the front tires, while negotiaing a corner, and the front wheels cannot generate enough grip to turn the car. A car with this condition is said to be “tight” or to have a "push".

oversteer:Condition where the front wheels of the car have more grip than the rear tires while negotiating a corner, often resulting in a spin. A car with this condition is often referred to as being "loose".

[OZGOD]

This is understeer

This is oversteer

Basically, when you turn into a corner, oversteer is when the car turns more than you expected and understeer is when it turns less than you expect.

[vinny.dtw]

And to realize that awd's tend to understeer alot, hence the stiffer springs, and larger sway bars in the rears to compensate for it. And having a heavy front end car also doesn't help the understeer. But in all honesty, for daily driving, you would not have a notable difference, untill you go to the track, and take your car to the limit.

[Doss]

Most manufacturers "build in" understeer as it is a lot easier for the average driver to deal with than oversteer. Oversteer often causes panic (or a big smile for people like me).

The simple concepts are this:

Understeer - you turn the steering wheel and the vehicle heads straight.

Oversteer - you turn the steering wheel and the rear "swings" around faster than the desired input demands (imagine a what happens in drifting (extreme case)).

Chances are you will never notice these unless you are pushing the car really hard (even harder than some of you guys think you push on the streets). There is the exception though of snowy, icy, or wet road conditions where this can become a problem.

<Tone = informative>

[NyteEscape]

hehe, i like oversteer w/ snow and esp off....

[mobigray]

Most manufacturers "build in" understeer as it is a lot easier for the average driver to deal with than oversteer. Oversteer often causes panic (or a big smile for people like me).



I wonder why most people prefer understeer and panic with oversteer. I find it easier to control the car when it oversteer.

[Allwheel Driver]

I wonder why most people prefer understeer and panic with oversteer. I find it easier to control the car when it oversteer.

Because most people are not driving enthusiasts and have enough trouble pulling into a parking spot let alone controlling an oversteering car.

I guess the manufacturers think that it's better to have a dope go straight off and only wreck his car than to spin and take someone else out too.

[kashutu]

I like to my car to oversteer. I had regular rear sway bar, but i changed it with S4 sway bars. How else can you get your car to oversteer more?

[ungucpho]

coil overs

[Doss]

There are several ways to get your car to oversteer:

Lower traction in the rear (different tire compounds/sizes)
Increase the tire lateral load transfer distribution value (most of the time all you need to do is make the rear sway bar stiffer than the front one)
Increase power and, for our cars, power distribution to the rear (commonly used technique is power oversteer)
Change the weight distribution of the vehicle (this is very tricky b/c it is a conditional oversteer problem related to accelerations)


There are a few other ways, but I think you get the point.

Oversteer is not as easy to achieve on AWD vehicles as the dynamics are greatly effected by several factors.

On RWD vehicles, simply adding more power is usually an easy fix.

On FWD vehicles, you should concern yourself more with fuel efficiency and grocery getting than these things. LOL (sorry, had to say it)

<Tone = informative, slight jabbing>

[Seire]

Understeer is when the driver is scared.
Oversteer is when the passenger is scared.

[mobigray]

This thread is making me want to sell my front trash and get my old mustang back.... shit.... but then again fuel efficiency and grocery getting is on the top of my "to do" list nowadays...

[47Ronin]

best way to get oversteer is to get bald tires -

[int2str]

Understeer is when the driver is scared.
Oversteer is when the passenger is scared.

LOL

Best explanation I've seen to date!

[int2str]

In addition to what Doss said, you can also shift power distribution towards the rear to get more oversteer from an AWD car.

A different center differential can do the trick on our cars.

[Doss]

In addition to what Doss said, you can also shift power distribution towards the rear to get more understeer from an AWD car.

A different center differential can do the trick on our cars.

Not following, more power to the rear usually ends up in oversteer, not understeer (rear becomes more likely to break loose).

I'm not saying it isn't possible, but you might have to elaborate more on other settings required to do so.

<Tone = slightly confused>

[gotquattro]

Understeer: Your facing the wall when you hit

Oversteer: Your facing away from the wall when you hit




Unless it's raining...

[int2str]

Not following, more power to the rear usually ends up in oversteer, not understeer (rear becomes more likely to break loose).

I'm not saying it isn't possible, but you might have to elaborate more on other settings required to do so.

<Tone = slightly confused>

Sorry, I corrected my post.

You were explaining how to get more OVERsteer from an AWD. I used the wrong term in my reply. It's fixed now.

Sorry for the confusion.

[47Ronin]

i still stick with the bald tires routine - plenty of steering in at least one direction

[Blindsay06]

Not following, more power to the rear usually ends up in oversteer, not understeer (rear becomes more likely to break loose).

I'm not saying it isn't possible, but you might have to elaborate more on other settings required to do so.

<Tone = slightly confused>

i forget who, but is it stasis that makes a different center diff. for our car to make the torque split approx, 30/70 (70 rear) wouldnt that help with generating some more oversteer?

[gotquattro]

Is there any reasonable ability to make noticeable changes on a street car with just changes in tire pressure? Say 35 lbs in the front and 40 lbs rear, making the rear break loose easier?

[47Ronin]

Is there any reasonable ability to make noticeable changes on a street car with just changes in tire pressure? Say 35 lbs in the front and 40 lbs rear, making the rear break loose easier?

break loose? you can just unscrew your lugs - something will break loose

[NyteEscape]

stasis has a center differential that allows up to 4:1 power distribution, which is around 80&#37; to any side.

i dont know if that's 80% to any wheel, but im sure it's atleast any side.

[HeHateMe]

This thread is making me want to sell my front trash and get my old mustang back.... shit.... but then again fuel efficiency and grocery getting is on the top of my "to do" list nowadays...

Yeah all of us FWD owners should just kill ourselves according to enlightened people like Doss.


<tone who gives a fuck>

[Doss]

Is there any reasonable ability to make noticeable changes on a street car with just changes in tire pressure? Say 35 lbs in the front and 40 lbs rear, making the rear break loose easier?

Actually, yes. You have to experiment a whole bunch to figure it out though. Using simple logic, your way should work (and is exactly how I'd start out).


What's really odd is that on the Cobra I raise the pressure in the rear higher than the fronts to reduce oversteer. Yes, it sounds counter-intuitive, but it works. I learned this from a national AX racer who runs Corvettes. I was out of options, so I listened. Crazy enough, it worked. Go figure.

Stasis does have a center diff that is biased towards the rear and it should help a little with inducing oversteer. The problem is you need a lot of torque (not high RPM turbo-torque only) to consistently produce oversteer. Yes, I do realize drift cars use turbos, but they have a lot of off turbo power as well.


You could do the same with spring rates, but then again, that'd be a lot of experimenting.

<Tone = informative>

[MikeWasHere05]

Understeer is when the front of the car hits the wall.
Oversteer is when the rear of the car hits the wall.
Horsepower is how fast you hit the wall.
Torque is how far you take the wall with you.

[n.d.]

"Stasis does have a center diff that is biased towards the rear and it should help a little with inducing oversteer."

Keep in mind that a center diff alone won't bias the power rear only under extreme cornering. Keep in mind that Audi's will still do the VW lean with a wheel in the air. At that point the center diff becomes an open diff. What I ran was a rear limited slip as well and that helped keep the power to the rear under throttle, wheel in the air or not. There's other things as well that you'll need to help get the A4 to rotate. Along with spring rates (a lot of testing to get that one right), sway bars, diffs, don't forget alignment settings. Anyways, that's what I did to get power-on oversteer. I used to run a silver Stasis/Streetwerke tuned A4 that was pretty well-tuned. My brother and I also use the same principles for our DSP Impreza.

[Raus]

Understeer is when you grab the steering wheel by the bottom, and oversteer is when you got your hands on the top.

Our cars understeer a little, however your goal should be to make it more neutral by tuning the suspension to make the car a little more rear biased. Wanting it to oversteer defeats the purpose of what quattro is all about.

[A4TL]

drift cars used those lame "stretched" rubber and chitty compound tires to induce oversteer. put some kelly brand tires in 205/35/17 on your rears and i bet it will oversteer alot easier :)

i still think its cholo style but the "poke" people get pissed. i guess its from chillin on the el camino real for so many years of my childhood. lol.

Sadly only the S4 (esp B5) will have to power to truly enjoy oversteer. our clutch would die before it ever happened lol. cept on snow :) then your power steering would die

[Amze]

Yeah all of us FWD owners should just kill ourselves according to enlightened people like Doss.


<tone who gives a fuck>

Please do, you embarrassing souls. You FWD owners must be the wives in the relationship.. Or so I hope




<tone = serious, dead serious>

[HeHateMe]

Amze, I don't give a fuck what you think whatsoever.


<tone= Amze should go eat a dick>

[Doss]

Yeah all of us FWD owners should just kill ourselves according to enlightened people like Doss.


<tone who gives a fuck>

That's a totally ignorant statement. FWD has its purposes. To me though, none of them translate into something I want. So, I will punch the kidneys of FWD owners in jest.

I do not claim to be "enlightened" as you say, but I do have a wealth of knowledge that I am willing to share with those that care to listen.

FWD is great if you're a manufacturer or having every extra cubic inch of room in your cabin is essential.

To me, I prefer to own vehicles with handling dynamics that are desirable by enthusiasts. This was my first dabble into AWD and I have already figured out that it isn't for me. Does that mean it is dumb or that I don't think anyone should own an AWD vehicle? Nope. Same for FWD. It's just not for me.

So, please, do yourself a favor and don't put words in my mouth.

I'll avoid doing the same to you.

It seems as though many of you on this board cannot accept criticism even as banter. You guys must have taken your ball home a lot as kids.

<Tone = retorting, clarifying>

[gotquattro]

I'm reading lots here about power-on oversteer, and balance.

How about the evil twin- trailing throttle oversteer?

I really haven't worked he A4 hard enough to have any input on this, but the GTI, being the hyper go-cart that it was, trailing throttle oversteer could be a god send and a heckuva lotta fun properly managed, and just as quick could have you facing the wrong direction at a bad time if you weren't careful.

Does quattro do the whole let off n rotate thing?

[martini]

vehicle dynamic definition. For a vehicle driving around a circle there are 3 scenarios:

1) As you increase speed around the circle (small increments), you need to increase your steering angle (turn wheel more) in order to maintain the circle - this is understeer

2) as you increase speed around the circle (small increments), you will reach a point whre you will have to decrease your steering angle to maintain the turn (rear end kicking out) - this is oversteer

3) as you increase speed around the circle (small increments), you maintain the same steering angle and hold the turn for all speeds the the tire's limits - this is neutral steer




manufacturers choose understeer because most drivers cannot control a car that needs a smaller steering angle at higher speeds (unstable vehicle). Neutral steer is 'ideal' but is very hard to attain. oversteer tends to be more fun than anything else...naturally.

[HeHateMe]

That's a totally ignorant statement. FWD has its purposes. To me though, none of them translate into something I want. So, I will punch the kidneys of FWD owners in jest.

I do not claim to be "enlightened" as you say, but I do have a wealth of knowledge that I am willing to share with those that care to listen.

FWD is great if you're a manufacturer or having every extra cubic inch of room in your cabin is essential.

To me, I prefer to own vehicles with handling dynamics that are desirable by enthusiasts. This was my first dabble into AWD and I have already figured out that it isn't for me. Does that mean it is dumb or that I don't think anyone should own an AWD vehicle? Nope. Same for FWD. It's just not for me.

So, please, do yourself a favor and don't put words in my mouth.

I'll avoid doing the same to you.

It seems as though many of you on this board cannot accept criticism even as banter. You guys must have taken your ball home a lot as kids.

<Tone = retorting, clarifying>

Do myself a favor and don't put words in your mouth? LOL, that's funny. Sure thing.