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Hey i was just reading around trying to find out about camber and what not, when i stumbled on this, and i was wondering if anyone had seen it B4

Oversteer is a phenomenon that can occur in an automobile which is attempting to turn. The car is said to oversteer when the rear wheels do not track behind the front wheels but instead slide out toward the outside of the turn. Oversteer can throw the car into a spin.

Understeer is a term for a car handling condition during cornering in which the circular path of the vehicle's motion is of a markedly greater diameter than the circle indicated by the direction its wheels are pointed. The effect is opposite to that of the oversteer and in simpler words under steer is the condition in which the front tires don't follow the trajectory the driver is trying to impose while taking the corner, instead following a more straight line trajectory.


Component -> How to Reduce Under-steer -> How to Reduce Over-steer

Front shock absorber - softer - stiffer
Rear shock absorber - stiffer - softer
Front sway bar - softer - stiffer
Rear sway bar - stiffer - softer
Front tyre selection1 - larger contact area2 - smaller contact area
Rear tyre selection - smaller contact area - larger contact area2
Front wheel rim width or diameter - larger2 - smaller
Rear wheel rim width or diameter - smaller - larger2
Front tyre pressure - higher pressure - lower pressure
Rear tyre pressure - lower pressure - higher pressure
Front wheel camber - increase negative camber - reduce negative camber
Rear wheel camber - reduce negative camber - increase negative camber
Rear spoiler - smaller -larger
Front height (because these usually
affect camber and roll resistance) - lower front end - raise front end
Rear height - raise rear end - lower rear end
Front toe in - increase - decrease
Rear toe in - decrease - increase

1) tyre contact area can be increased by using wider tyres, or tyres with fewer grooves in the tread pattern. Of course fewer grooves has the opposite effect in wet weather or other poor road conditions.

2) These also improve road holding, under most conditions.

In addition, lowering the center of gravity will always help the handling (as well as reduce the chance of roll-over). This can be done to some extent by using plastic windows (or none) and light roof, hood (bonnet) and boot (trunk) lid materials, by reducing the ground clearance, etc. Increasing the track with "reversed" wheels will have a similar effect, but remember that the wider the car the less spare room it has on the road and the farther you may have to swerve to miss an obstacle. Stiffer springs and/or shocks, both front and rear, will generally improve handling, at the expense of comfort on small bumps. Performance suspension kits are available. Light alloy (mostly aluminum or magnesium) wheels improve handling and ride as well as appearance.

Moment of inertia can be reduced by using lighter bumpers and wings (fenders), or none at all.

 
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This is a great post. Good find.

 
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i believe this had been widely discussed, but still a good heads up. anyways, if someone is gonna mess with camber, it's ussually to induce more "oversteer" other wise stock setting would be ideal. in the case of our car FWD, oversteer is an uncommon term. ussually it's more oversteer-neutral that is desired. anyways for those just reading, this it still a great easy layout of how alignment, weight and pressure effects our car's characteristics.

 
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thanks, but the thing was i notice when i take turns (on and off ramps) it feels like the back of my car is wobbling/trying to make me spin out, so i thought it was the whole oversteer tryin to spin me out. Yea i know i could just slow down and that would be that, but in the future when my car is faster, i dont want to worry about spinning out, so thats when i just started searchin the web. but yeah, thanks for ur input

 
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nice find!

 
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IF you dont want ot have to worry about the car spinning... Then Teach your self to drive differently.

For example, My car is preped for autocross and could be considered Very tail happy (oversteer prone). However, since I've spent 4+ years learning to drive properly and competing with the car, when I'm on the street the only time the rear end slides is when I want it to or when I do something stupid. Luckly i've enough seat time to correct for it.

Now, you can tune the car to be more understeer prone, and thus more stable and easy to drive. However by doing so you are forceing your car to be slower in any given turn.

And given that about 90% of what a car does at any one moment (oversteer or understeer) is caused or influenced by the driver... I'd say that you have much more to gain by learning to drive properly then to try and tune the car to make up for improper driving.

 
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So before u did any of this to your car "Eibach sportline springs, Hotchkiss 25.4mm Rear Anti-roll bar, 03 Civic OEM front anti-roll bar (15.9mm) Energy suspension Bushings (Front only)" you never had a problem with the back of your car feeling like its wobbling taking a off ramp at a higher speed than posted? Yea i could do what u did and spend alot of time (4+ years) learning to drive properly or what not, but all that just so i can take a ramp faster... i don't plan on autocrossing it out like u and some other members here, so wouldn't a few mods be more suited for my application?

 
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If your rear end wants to spin out during an on ramp; your entry speed is too fast or you're braking too late. Slow down and accelerate through the turn, you'll be surprised how the rear wants to stick to ground with a sway bar by doing this. And I'm sure you know not to brake during the turn you'll just lose more traction as you unload the rear shocks.

 
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ok, but im kinda lost with the "stick to the ground with a sway bar by doing this" so are u saying i would get this response with a sway bar? or just by keeping my stock suspension and just slowing down a little more before the turn and accelerating through it?

Thanx for the info also

 
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Sorry I should have been more clear. I upgraded my rear sway bar to 17mm (EP3 swaybar). I have a 2003 EX so the front is 15.9mm and the stock rear is 12mm. So as you posted earlier, a thicker rear sway bar will make the car more prone to oversteering but since the rear is not that much bigger than the front on my setup it makes the car a bit more neutral rather than understeering with the factory rear sway. I didn't want to go 19mm bc I thought that would be too big but alot of ppl love it. The 19mm seems to suit those with 2001-2002 civics with the bigger front sway bar. I hope that clarifies things. Get the sway bar you'll def feel the difference, one of the best cheap mods you can do to the civic.

 
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i think what he mean was that with a thicker rear sway bar, he can reduce throttle, then coming out of the apex, he accelerates and that causes the rear to keep traction, as oppose to normal reflex to brake that would only make it worse when it unload the rear shocks to lose more traction., i hope i'm making sense here

 
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With an 01 ex you have a huge front sway bar and a small rear so unless you're inducing the oversteer it should understeer before oversteer. Does it feel lose when you turn in or mid corner or the exit? When are you braking? When do you stop braking? Do you turn in while on the brakes?

 
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ok i see, thanks you guys for the input.

but what about what zzyzx said? when he was saying its all 90% what the driver does. With a rear sway bar allow me to take the turn faster or slower?

 
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It feels loose like midway throught the turn, and the rest of the way through the turn. I never brake through the turn at all, only when i enter, and i think im going way too fast i slowly brake then just either maintain a constant speed or accelerate through the turn. But yeah i dont brake throught the turn.

 
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So you brake when you turn in (ie appying the brake and turning at the same time) If you're on the brakes when you enter that's why you're getting oversteer. Brake in a straight line before the turn, get off than turn in and accelerate out. Theoredicly you should be able to take a turn faster with a larger rear sway bar but it all depends on how you take the turn. If you're getting oversteer now a larger rear sway bar is probably going to make it worse.

 
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No thats what i mean. I brake approaching the turn, not going into the turn. sorry if i accidentally said i brake coming into the turn, i mean the approach.

 
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Hmm well I'm at a loss than. Your alignment might be out of wack or your rear shocks could be blown really bad and they can't keep up with the springs. Other than that I dunno. Maybe zzyzx or boilermaker have an idea.

 
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Or he's trying to take a turn at 100mph lol. Also, how is the tread on your tires. Poor tires are a major reason for poor traction.

 
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^Could be but usually when you come in too hot you understeer.

 
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Ya you're right MisterFrankieJ I'm at a loss myself.

 
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just got my tires this fall. And as for the turn im taking it at like 65-75 somewhere in that range. and i think the turn is marked at 45 or so. But yea for the first half i am good, then like midway through, everything in the rear is kinda shaky. Imma get a alignment, and balance and rotate pretty soon to see if thats the thing, i doubt it tho... hmmm. i have been planning on buying a rear sway for a while now, so im also gonna try that out. Well, guys thanx for your input.

 
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What I'm trying to say is that Given any car in any particular turn can be driven so that it tends to oversteer, just as the same car in the same corner can also be driven so that it tends to understeer. Now a car can be tuned to tend to do either more naturally, but ultimatly the cars oversteer/understeer balance is most greatly influenced by you the driver.

so, given that...

What portion of the turn is the car tending to oversteer, and more importantly, what are you as a driver doing at that moment? are you accelerating? Brakeing? Coasting? are you running nutural throttle (nither accelerating or decelerating)... are you being smooth whit the steering wheel or are you spikeing it in to these turns? Ect ect ect....


Edit: stiffining up the rear bar alone will increase the cars natural tendency to oversteer. So if the car is oversteering too much for you now, getting a 19 or 22 mm rear bar will only make it worse.

 
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Ok heres what all happens at this turn, as i approach the turn, i either slow down or coast at the speed i'm at and get into the outside lane. Then as i actually get into the turn, i'm at neitral throttle, but because its downhill sorta i'm speeding up. Now i eventually change lanes into the inner lane like 1/5 of the way into the turn, and hug the inner line, and as i keep it smooth on that line, maybe 3/5 into the turn the back starts to wobble a little, then maybe 4/5 into the turn, i usually start accelerating and then coming out of the turn like once the road starts straighting out, the wobbling then subsides. Do u need n e more info?

 
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Ok, so when in that turn does the car start to oversteer? when you enter, mid turn or as you are accelerating out of it?

 
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mid turn, thats when it feels like my car is loose.

 
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good find. info is helpful in understanding what everything means.

 
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Interesting. Typically a FWD car will only naturally oversteer when it is decelerating, either from you being on the brakes (trail brakeing) or from you not being on the throttle, which causes a bit of engine brakeing. Engine brakeing basicaly acts as if you are applying the brakes to only the front wheels. So if you are coasting through the middle of the turn (Not being on the brake or throttle) then that could be the cause of your instablility. other wise, its time to start looking for worn parts (bushing compliance can cause toe change under load) and to check/optimize your alignment....

 
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With the turn having a downhill slope, it also makes the car want to oversteer doesn't it? Since the weight is being transferred to the front, then add the engine braking means less weight on the rear and therefore oversteer.

 
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haha awesome post bro.

i learned something today =]

 
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ok well then its time to hike up the car and start looking for clues. Imma take that turn again today and a few more to completely asses the prob and try different things going into and throughout the turns. but yea guys thank you for the info