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Old 04-12-2006, 11:37 AM   #1
machined
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Why is understeer better for the average driver?

I've always heard this was true.
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Old 04-12-2006, 11:39 AM   #2
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easier to correct than oversteer.
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Old 04-12-2006, 11:50 AM   #3
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Exactly. It's easier to regain control of the vehicle when you're skidding facing forwards than it is skidding facing backwards.
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Old 04-12-2006, 12:17 PM   #4
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I'd much prefer the back end to slip out than the front just continue to push forward though...?
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Old 04-12-2006, 12:18 PM   #5
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buy a car with oversteer then.
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Old 04-12-2006, 02:31 PM   #6
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Originally Posted by thirstydude
I'd much prefer the back end to slip out than the front just continue to push forward though...?
You are in the minority, and auto manufacturers sell to the majority. Do you think the average Joe or Soccer Mom would prefer the back end of their car to come around if they took the freeway offramp 5 mph too fast? Imagine the lawsuits that would come from people spinning out all over the place if cars were setup to oversteer. Most people would consider that poor design and a faulty product (the main reason the Chevy Corvair's lifespan was so short).

With understeer, it's easier to recover by gently lifting off the brake or straigtening the steering wheel until traction is regained, and continuing on your way.
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Old 04-12-2006, 02:48 PM   #7
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That's scary lol. In a panic most people don't think to do that and just keep on sliding straight. I've always thought was Corvair was pretty cool lookin. Poor car..
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Old 04-12-2006, 06:25 PM   #8
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Most people don't have the ability to correct oversteer. Either they dont understand the concept of steering/looking where you want to go, they're not quick enough, or they hit the brakes which only exaggerates the oversteer into a spin.
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Old 04-12-2006, 07:10 PM   #9
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If you really want some oversteer, the easiest way would be to ensure that your REAR tyres have something like 3-8psi LESS air than your fronts (yes, this induces oversteer and not understeer as you might think).
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Old 04-13-2006, 08:50 AM   #10
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Quote:
Originally Posted by TaiFong
If you really want some oversteer, the easiest way would be to ensure that your REAR tyres have something like 3-8psi LESS air than your fronts (yes, this induces oversteer and not understeer as you might think).


Can you elaborate more on that? I always though more air in the rear would promote oversteer?


Edit: I actually prefer oversteer as well... <3 teh drift
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Old 04-13-2006, 12:47 PM   #11
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Oversteer is exaggerated by lifting or applying the brakes - 99.9% of people hit the brakes when they panic for whatever reason. If you begin to sense that you may loose the backend, and apply the brakes, the wieght transfers forward off the rear and the rear end comes around. When I hear that someone "spun out" in a street "accident", my assumption is they were nowhere near the limits of traction, and hit the brakes "making" themselves spin out, when they probably could have driven out of the situation if they had a clue.

For understeer, you correct it by lifting and getting the weight to shift to the front providing more traction and correcting the understeer.

For those of you who think you like oversteer, I would ask you to go to a DE and run through a few very high speed corners, and then tell me you want oversteer. I can tell you the last thing I want in Turns 12 or 1 at Road Atlanta is a car with a twitchy rear end................ Plenty of 911s have found the inside wall coming out of both of those corners - at the limits, it's "don't even think about lifting", but the good thing is with a bit of understeer you have a chance if you have to feather the trottle a bit, with a car with oversteer, your saying hello to the inside wall as soon as you come off the gas peddle.

Unless you're Bill Auberlin, you're probably much better off with a car with understeer..............
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Old 04-13-2006, 12:49 PM   #12
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oversteer might be fun sometimes, but i hate chasing the tail end of my car all over the place while trying to manage a quick lap.

if you guys really love oversteer, you could set up your cars to have a more oversteer oriented bias through tire sizes, sway bar settings, and shock settings.

go for it.
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Old 04-13-2006, 06:57 PM   #13
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Oversteer at 20-30mph is fun. At 80mph it is NOT fun. At higher speeds, your suspension is less responsive to corrections. What tends to happen is you crank in the correction on the wheel and nothing happens since the suspension can't respond fast enough and you crank even more on the wheel as a result. As soon as the suspension catches up with your steering input, you've got too much opposite lock on the wheel and you get snapped around going the other way. It's a much faster and more violent spin. I'm glad it happened to me at the track with no walls around.

Understeer is safer for the untrained driver. The natural response for most people is to lift and/or brake when they've lost traction. For understeer, that is the correct response. For oversteer, the correct response can be to either lift slightly, stay on the gas, or give it more gas, depending on what caused the oversteer.
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Old 04-14-2006, 12:56 PM   #14
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Originally Posted by Idrivea328I
Can you elaborate more on that? I always though more air in the rear would promote oversteer?


Edit: I actually prefer oversteer as well... <3 teh drift
I should say first that inducing oversteer using the tire PSI method is a nice way to get a stock, understeer-prone car (such as our 3ers) to feel a bit more neutral. Actual twitchy oversteer is not fun to deal with.

Anyway, back on the subject. The tyre sidewalls are the key factor for this effect. When your rear tyres have less air than your fronts, your rear sidewalls flex to a greater degree, causing instability of that tyre relative to the front. It is true that at these levels, a tyre with less air has a greater contact patch, and therefore more grip, but the sidewall flex overcomes this.
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Old 04-14-2006, 10:27 PM   #15
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Any tire has an optimum pressure it wants to run at on any given car and suspension. Anywhere above that optimum pressure will reduce the tires grip as well. Back when I autoxed a FWD car sometimes I'd run Giant pressure in the rear tires at events to get the car to rotate as well. Either way under or overinflated tires is a rather poor substitute for actually coming up with a good setup.
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Old 04-15-2006, 02:31 PM   #16
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