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全部话题 - 话题: understeer
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s*****8
发帖数: 606
1
来自主题: _Auto_Fans版 - understeer/oversteer 问题
有个事一直想不明白,来请教一下。假如车是前置后驱,想减少understeer,所以就要
增加后轮的slip angle,举几个例子
1-重心后移,这个很好理解,增加后面的压力来增加slip angle
2-后悬挂调硬,过弯的时候如果悬挂越软,外侧的轮子的受力就越大,如果将悬挂调硬
,两侧的受力分布会更平均所以外侧轮的受力会减小,因此后轮slip angle就会减小,
那么为什么还会导致oversteer呢???
3-降低后轮胎压和用窄胎也可以减少understeer,但减少胎压增大接触面积不是跟用窄
胎相违背么??而且autox的时候我问过好几个老油条,他们都说是增加后轮胎压来减
少understeer,谁能帮忙解释下这个??难道induce和cause oversteer不是一个意思
e********y
发帖数: 350
2
来自主题: _Auto_Fans版 - understeer/oversteer 问题
从最理想的胎压开始,增加和减少胎压都会降低traction。增大会减少接地面积,减少
会让sidewall变得更软,转弯抓地力下降。一般autox都会增加,因为降低胎压后摩擦
sidewall伤不起。
还有我不是很理解第一条,重心后移会增加understeer才对吧,一般多trail braking
可以帮助减少turn in understeer
另外一个减少understeer的办法就是调整前后的negative camber差,例如前-3 后-1.5
,一般的ff赛车都会用这招.
o******o
发帖数: 1205
3
来自主题: _Auto_Fans版 - understeer/oversteer 问题
Understeer是因为前轮抓地不足,如果你weight transfer到后面,前面会更不足.
其实车辆的balance是相对你需求的,如果你是想提高操控性,可以考虑降低后面的抓
地力来提高车辆整体balance。但是如果你要下赛道或者某种程度上提高整体成绩,很
多人的误区就是降低部分性能来提高感觉上的好操控,你应该把大多的注意力放在增加
前轮的抓地性能而不是减小车尾的性能,这样成绩上是不会有什么提升的,反倒有可能
会下降。
减小understeer比较容易的方法就是增加前轮camber,软化前轮避震,比如减小避震
rebound,换软一点弹簧等,因为抓地需要body roll, 太硬了body roll会减小,
weight transfer也会受影响。另外就是加宽轮胎或者换更好的胎,这是比较容易实现
的,至于tire pressure要看轮胎,不同轮胎的最佳工作状态相对应的胎压和胎温都不
同。
最后就是操控,说到底车是人开的,很多时候没有办法在调校上改变,司机有必要去适
应这台车的特性,前驱车说到底understeer都会有,只是相对的好坏,所以还是需要人
去改变驾驶风格mat... 阅读全帖
t******k
发帖数: 5617
4
understeering对于普通人来说更好控制,因为大部分人第一反应是踩刹车,
understeering的时候踩刹车不会有很大危险,而oversteering的时候踩刹车就飘了。
。。
q**j
发帖数: 10612
5
前轮压力不够要under,后轮是Over。所以前轮车一般是under,后驱车会oversteer。感
觉understeer会更危险。转不过弯会飞出去,但是一般都说over危险。请问原理是什
么?
q**j
发帖数: 10612
6
多谢回复。understeer是前轮摩擦不够。前驱车前面重,好像更应该oversteer, 但是
这个好像和平常说的不一样。请问怎么回事?
t******k
发帖数: 5617
7
这个是这样的,正因为前驱车重量集中于车头,因此前轮受到的惯性更大,在转向时,
需要更大的摩擦力克服惯性,一旦轮胎抓地力无法克服侧滑惯性,车头就会像弯道外滑
动,从而使转弯半径加大,形成转向不足。
另一方面前驱车的前轮既是驱动轮又是转向轮,一旦打滑无法控制转向,所以更容易出
现understeering
a****h
发帖数: 1012
8
Oversteer,要拉回来,必须踩油门,然后反打方向盘。。。然后这对操控不熟的新手
来说,作出这样的反应是比较困难的。。。
understeer,要拉回来,只要减速就行了。。。。这比较容易,也比较符合一般人的第
一反应。。
如果要体会的话,去跑一跑场地就明白了。。。就是在停车场里面,摆圆锥桶做赛道那
种。。
s*****8
发帖数: 606
9
来自主题: _Auto_Fans版 - understeer/oversteer 问题
thanks all for the reply. sorry cannot type the Chinese.
There are tons of the methods to tune the car to understeer/oversteer, but
all start from the slip angle, I was trying to understand the slip angle so
I can tell how to tune the car when im driving it.
I am thinking there are 2 slip angles, one is the slip angle the tire
designed for, the other is the way to create slip angle(SA) by the tire. I
dont know if it is right or wrong.....
For example, front engine rear wheel drive car, if the ti... 阅读全帖
u******w
发帖数: 1882
10
来自主题: _Auto_Fans版 - understeer/oversteer 问题
这个是是对轮胎特性的误解。understeering和over在本质上的定义是比较前后轮的
slip angle,而slip angle是只要有侧向里就会发生的,不一定用等到侧滑,因为轮胎
不是刚体。也就是说比如车在前进时哪怕你用人力在侧面推一下车,前后轮都会产生侧
偏角(slip angle),只不过很小。而转弯时就相当于有个侧向力作用,这个时候前后
轮的侧偏角差别决定了整车是过度还是不足转向。
当重心后移时,转弯时相当于后轮受到的侧向力变大,所以后轮的侧偏角变大,整车更
趋于过多转向。
如果你真有兴趣,建议看看《汽车理论》,其实就是汽车动力学,国内车辆专业的必修
课,里面有我说的那个公式
s*****8
发帖数: 606
11
来自主题: _Auto_Fans版 - understeer/oversteer 问题

this is for track, I tried different tires setup and front cambers last year
, it did resolve understeer issue.
what do you mean by '很多人的误区就是降低部分性能来提高感觉上的好操控'?
how to understand the rebound setup? I will install the coilover that can
adjust rebound this year, im going to soften everything to learn the
suspension and tune little by little, but i have a hard time to find how
rebound setup related to compress setup, and how can tell the rebound is not
setup correctly?
e**n
发帖数: 1326
12
来自主题: _Auto_Fans版 - understeer/oversteer 问题
"很多人的误区就是降低部分性能来提高感觉上的好操控"
我试着解释下:damping设置理论上应该保证最佳的车轮贴地性,车轮吃坑/bump后应该
要最快的回到原位但是不能弹跳(under damped)。如果over damped车轮归位的时间会
变久。两种情况都会导致抓地力的损失。
但是同时也可以调节damping来控制瞬态的weight transfer来改善车子的操控性。比如
说spring/rollbar设成静态的understeer,但是通过调节damping来提供瞬态的neutral/
oversteer来改善turn in. 这样调出来的damping rate和提供最佳车轮贴地性的
damping rate往往就不相等,那个时候就要在两个之间作取舍了。

year
not
s*****8
发帖数: 606
13
来自主题: _Auto_Fans版 - understeer/oversteer 问题

I did road course, autox and drift, I understand how to use throttle/brake,
tire, camber to setup/induce understeer/oversteer, but i want to find out
theoretically why they happen, which i believe origin from the tire slip
angel, that is the thing confusing me.
Thanks for all your reply, I got some good books, I will read them and see
if I can find out the answer.
t*****0
发帖数: 264
14
来自主题: Automobile版 - [合集] 四驱系统详细指标
☆─────────────────────────────────────☆
fjcruiser (FJ) 于 (Fri Jan 21 01:47:10 2011, 美东) 提到:
四驱是一个很复杂的概念,广大不明真相的群众很容易看一些无良厂商制作的
youtube录像受骗上当。一个四驱车到底怎么样,*至少*要从以下八个方面看:
公路驾驶指标(AWD)
AWD类型: 适时(on-demand) / 全时 (full-time)
中差: 无/ 开放 / 限滑
后差: 开放 / 限滑 / 其它(SH-AWD)
前差: 开放 / 限滑
越野驾驶指标(4WD, 4x4)
低速档: 无/有
中差锁(分动箱锁): 无/有
后差锁: 无/有
前差锁: 无/有
下面,我们以一些本版常讨论的车型为例,分析一下这些四驱车到底都是什么货。
(待续)
☆─────────────────────────────────────☆
fjcruiser (FJ) 于 (Fri Jan 21 01:57:46 2011, 美东) 提到:
四驱系统案例:Gra... 阅读全帖
X***9
发帖数: 7385
15

我还奇怪怎么没人问被捧成神的斯巴鲁的4驱呢,的确有太多的人觉得斯巴鲁的4驱很好
,或是考虑买斯巴鲁的原因就是因为他的4驱。
我个人认为和本田的不在一个级别,甚至不如奥迪或宝马的,当然有不同观点可以补充。
首先本田的sh awd可以通过电磁多片离合后桥差速器自主,自由的任意调整后轮的扭力
输出,比如说从一侧的100到0,或另一侧的0到100,实现实时无极自由分配。那么这个
系统首先符合了大家说的torque vectoring system 扭矩矢量分配系统
抛开有没有本田这么自主自由的分配不说,先说能不能分配,斯巴鲁宣布从15款wrx才带
torque vectoring的功能,好像15款还有几个也上了,斯巴鲁叫 Active Torque
Vectoring
斯巴鲁官网是这么介绍的
All new generation WRX and WRX STI models now add Active Torque Vectoring to
their VDC technologies.
ACTIVE TORQUE VECTORING SYSTEM: - reduces cornering... 阅读全帖
T******g
发帖数: 21328
16
来自主题: Automobile版 - 斯巴鲁的太公四驱?
什么不懂的工科男也很多的,比方您这位。我更不是什么大妈。不过大妈比你懂的多的
还是有的
那我就给你科普一下,fwd路滑紧急避险的问题是understeer,你看视频里面撞到障碍
物都是understeer严重来不及调整。crv好一些,escape最差。说明他们是awd系统里后
轮驱动部分和车整体调教不行,不能从understeer correct回来。
forester awd系统调教的好,路滑紧急避险操作比较neutual罢了,容易躲过障碍物然
后回到自己车道,防止和对面车冲撞。
这些车同一个车的四个轮子都是同一型号的没有差别的,同时换一个牌子,并不能明显
改变understeer/oversteer behavior。
这些车都是consumer cross shopping的同一个类型的,大小,车重价格都差不多。
R*N
发帖数: 2173
17
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Scroll Down for Quick Reference ... 阅读全帖
r********a
发帖数: 139
18
来自主题: _Auto_Fans版 - 帮我说说GTI (08-10)坏话:P
你是对的,我被rx8论坛上的那些讨论误导了。。。>.< 有人说他的rx8用的是
GNK super LSD,是helical的. 如果是helical的,那么肯定是torsen类型的。
在GNK自己的网站上,区分了super LSD和helical LSD,那么前者就只能是cone cluch的了,开发两套torsen-type没有意义。
不过,torque-sensing cluch LSD不意味着会带来understeering, 同样torsen type LSD也不表示可以减小understeering. torque sensing LSD用在前驱车上的目的是为了在加速的时候消除power steering,或者说为了更好的出弯,而不是为了帮助入弯。
其实恰好相反,入弯的时候前驱车反而怕LSD起作用,如果diff被limited了,understeering只会更加严重。有一类比较极端的clutch LSD(通常是aftermarket,给那些玩power drift的人用的)可以在入弯的时候起作用,如果用在FWD车上,会增加understeering,这可能是你说speed
s*****8
发帖数: 606
19
来自主题: _Auto_Fans版 - 在美国怎么在赛道上开?

Forgot to answer this question “还有你如果是autocross新手但是车子改成这样子
了,就已经没啥竞争力可言啦,还是应该用原厂的,不过350z跑autocross本身也不是
很好,可能跑赛道会更适合。”
Let me tell you what mods I did and why I did that and what result I felt
from these mods.
- Supercharger. Came from previous owner, I want to do supercharger
anyway. Main reason is to learn the F/I car.
- Oil cooler. Came from previous owner, I said that is a must for
aftermarket supercharger car.
- Suspension mods:
o Cusco sway bars. It will help to reduce body r... 阅读全帖
l*x
发帖数: 396
20
来自主题: Automobile版 - 有没有两座的小跑推荐
在轮胎打滑的情况下,oversteer比understeer好控制多了。一般开赛车的没几个会喜
欢understeering。车厂把量产车调到比较understeer是为了在极限下更安全.一但轮胎
打滑,FWD很难控制. RWD可以漂移过弯,也就是说可以给车手信心来push到极限.

oversteer
i****x
发帖数: 17565
21
来自主题: Automobile版 - 有没有两座的小跑推荐
I'm tired of arguing with one who doesn't accept basic facts. you said some
people argue without going to track but obviously you are one and btw, I do
go to track.
good rwd car does NOT oversteer in corner unless you give too much gas. If
it does, you can counter steer and ease off gas a bit to save it and
cornering becomes neutral again. when you enter a corner too fast rwd car
may understeer as well but just give it more more gas you can fix the under
steer. so for trained driver, rwd is tota... 阅读全帖
r******d
发帖数: 1879
22
来自主题: SanFrancisco版 - JP Morgan 加入房托队伍
摘要:
- Median price to household income ratio is history low at 153%
- history low mortgage interest
- Median mortgage payment is only 78% of median asking rent, and it used to
be 105% before 2005
- new house price is only 25% higher than construction cost, and it is twice
as much in 2005
全文:
With the debt crisis in Europe still unresolved and economic growth in the U
.S. sluggish, the capital markets continue to exhibit elevated volatility.
However, this does not mean that no investment opportun... 阅读全帖
m**********1
发帖数: 43
23
来自主题: _Auto_Fans版 - Skid pad 101
The following techniques are all based on FR/MR/RR cars, no FF cars (
actually they are just transportation tools, not cars).
In respond to your ?’s
Most of the cars are tuned to be biased to understeer for safety reasons. As
for normal drivers, understeer is easy to correct (just brake a little bit)
, and such compensation is human nature. However, oversteer is mostly seen
on high performance cars (explained later). People talking ‘understeer
scares passenger and oversteer scares driver’.
It is
T******g
发帖数: 21328
24
来自主题: _Auto_Fans版 - awd还有真假之分。。。?
LSD:
Quote:
Originally Posted by me
A few points because I think others have confused a few issues here.
The Torsen I used in 94 and I think some 95s is the original worm gear
design that every one loved. The Torsen II used in I think later 95 through
basically now (the later used a dif with a different name but it was the
same basic design) is a Quaife type helix LSD. The torque sensing name came
from the Torsen I dif which developed locking based on the torque applied to
the wheels, not based ... 阅读全帖
W*******d
发帖数: 446
25
来自主题: _Auto_Fans版 - 帮我说说GTI (08-10)坏话:P
You can't assume it will understeer just because it's FWD.
BMW 3 is set to understeer from manufacturer as well as most stock RWD cars
because it's safer than oversteer.
In fact, my GTI is very neutral with minimum body roll. All I did is a
larger RSB(24mm vs 22mm stock) and Bilstein damper since the stock on is
underdamped.
If I put the RSB at full stiff, it will oversteer first rather than
understeer if I am not careful.
i****x
发帖数: 17565
26
来自主题: _Auto_Fans版 - 后驱车真是难开啊.
前驱=不给油understeer,给油更understeer
后驱=不给油understeer,给点油neutral,过分给油oversteer
结论:熟悉后还是后驱好
不过mustang的live axle后悬本来就比其他后驱更容易打滑。后驱的确平常都是小心翼
翼的,下雨下雪我的标准都是转弯时绝不加速
V***b
发帖数: 3419
27
来自主题: _Auto_Fans版 - E90 vs F30 操控差异
toe in 的目的是减小后胎slip angle, 从而增加出弯的稳定性,高速过弯作用尤其明
显。带来的缺点是转弯半径会增大,后胎slip angle减小,understeering多一些。
toe out 相反,可以加快入弯角度,减小转弯半径,增加后胎slip angle,增加
overstering. (我这里说的都是RWD或者AWD啊)
一个车的后轮是调教成toe in还是toe out主要是看这个车干什么用和这个车的其他参
数。经常上赛道的车通常是入弯踩刹车出弯踩油门,toe in会增加一点转弯半径,但不
会带来过多的understeering,但出弯的稳定性大大增加,踩油门的时机也可以提前,
踩油门深度加大。总体上是受益的。
3系这种讲究操控的菜车,toe in就没必要了。因为过弯速度不会太快,入弯也不见得
踩刹车,所以toe in带来的更大的转弯半径和更多的understeering就比较明显了。
最理想的后轮调校是入弯toe out, 出弯toe in, GT-R (R34) 的HICAS系统就是这种,
HICAS其实是4WS, 但道理是一样的。
现在Porsche主... 阅读全帖
D***0
发帖数: 5214
28
来自主题: _Auto_Fans版 - 请教一下GOLF GTI 和 R
Still, this discrepancy was surprising given his frustration with the Golf’
s understeer and stubborn dual-clutch. “Into the corner, when driven at the
limit, the Golf R understeers a lot,” he said. “It is helped by some
light trail-braking to bring the nose in. In Sport mode the transmission was
not downshifting until I gave it the gas. Well, that’s too late. It needs
to already be in the gear.” 同样的文章后一段randy又说到
另外在MT评去年的最佳drivers car的时候 R排第九 副标题是 The R is for
Understeer
http://www.motortrend.c... 阅读全帖
r**********g
发帖数: 22734
29
来自主题: Military版 - Yahoo 评论
They spent 14 billion for the opening ceremony :(
@ Mike you really need to talk to the English coppers, they are very poorly
paid, my own brother is on duty dealy with the people attending and they
aren't getting extra pay.
0users liked this commentPlease sign in to rate a Thumb UpPlease sign in to
rate a Thumb Down0users disliked this commentLynn 2 minutes 43 seconds ago
Celebrating their Health Care, and the queen looks bored to death. I'm
excited. The build up was better then the real thing.... 阅读全帖
l****z
发帖数: 29846
30
By Paul Kengor
It's interesting that not only does Barack Obama need continued vetting, but
so do his biographers. The culprit is the same: the liberal bias that
dutifully protects Obama like white knights guarding the king's castle,
shamelessly tossing journalistic objectivity right out the window. As Sean
Hannity likes to say, when it comes to Obama's background, it has fallen to
us conservatives to do the job that the mainstream "Obama-mania media"
plainly refuses to do.
The most recent Oba... 阅读全帖
l****z
发帖数: 29846
31
来自主题: USANews版 - 伊利诺伊州负债累累
Apocalypse Illinois: IOUs Projected to Hit $10.5 Billion, $163 Billion
Total Accumulated Liabilities
Flat Out Broke
Illinois is in serious fiscal trouble. Unpaid bills will hit about $10.5
billion later this year, counting unpaid lotto winners and state university
bills.
Lotto is a small problem overall, yet symbolic of the mess the state is in.
Because Illinois has no current budget, the state does not pay lotto winners
. Instead it sends the winners IOUs. Yesterday, two Illinois lottery winner... 阅读全帖
I****h
发帖数: 33
32
要看路面的情况。
如果路面摩擦力小(比如雪地),那么请你千万在入弯前把速度减到位,然后在弯中千
万别踩刹车,匀速通过。
路面情况好的话,关系不大,凭感觉开就行了。另外跟你的车是前驱还是后驱也有关系
,比如万一出现understeer,也就是转弯半径过大,那么前驱的车应该踩刹车,而后驱
的车应该加速,对这些细节感兴趣的话,可以去看http://www0.epinions.com/auto-review-29AF-D5B5AC5-394D2268-prod5
quote:
If the car understeeers in the turn, you have to lift off the throttle and
slow down. In RWD car, if the car understeers in the turn, you can increase
the throttle (not before the mid corner!) and car will start oversteering,
correcting the trajectory.

要是
道踩
一大... 阅读全帖
g*******x
发帖数: 2158
33
来自主题: Automobile版 - 四驱系统详细指标
无语了.
看看2008版本的forester
http://www.distrocars.com/2008-subaru-forester
The Forester line features three versions of Symmetrical All-Wheel
Drive, all of which power all four wheels all the time and can transfer
more power to the wheels with the best grip. In all models equipped with
the 5-speed manual transmission, a viscous coupling locking center
differential built into the transmission case divides engine power
50:50. Wheel slippage at one set of wheels causes more power to shift to
the opposit... 阅读全帖
b*********n
发帖数: 2975
34
来自主题: Automobile版 - 四驱系统详细指标
since toyota bought subaru, forester slided into more rav-4 like, hehe

无语了.
看看2008版本的forester
http://www.distrocars.com/2008-subaru-forester
The Forester line features three versions of Symmetrical All-Wheel
Drive, all of which power all four wheels all the time and can transfer
more power to the wheels with the best grip. In all models equipped with
the 5-speed manual transmission, a viscous coupling locking center
differential built into the transmission case divides engine power
50:50. Wheel... 阅读全帖
i****x
发帖数: 17565
35
来自主题: Automobile版 - 科普贴——神奇的悬挂
维基百科说的很清楚
首先sway bar是跟独立悬挂相反的概念,在不侧倾时应该比较软,让悬挂基本上呈独立
工作的状态。太硬的sway bar,平常也影响悬挂的工作,就适得其反了。另外,如果前
后轮sway bar硬度差异较大,可能会让一个轮子腾空,对于后驱跑车是灾难性的。但是
很多四驱、前驱跑车比如civic type r、mitsubishi evo都这样设计,让一个后轮离地
,降低车尾抓地力,这样可以故意制造over steer,来抵消前驱和四驱车天生容易
understeer的趋势。
Because an anti-roll bar connects wheels on the opposite sides of the
vehicle together, the bar will transmit the force of one-wheel bumps to the
opposite wheel. On rough or broken pavement, anti-roll bars can produce
jarring, side-to-side body motions... 阅读全帖
j*********s
发帖数: 142
36
最后决定了Accord Sport,说说试驾的经历:
试驾是在12/26,正好下大雪,很可以测试车在雪天的性能。
先试了Accord Sport, 我开在S档,手动换档。对油门响应比较满意。加速有两个peak
,一个在2500转左右,另一个在5000以上。刹车踏板比较isolated,较软,电子辅助刹
车介入比较生硬。转向极轻,没有任何轮胎的feedback,但是很准很灵敏,微小的输入
就有输出。悬挂在家用车里可以说得上“硬朗”了。比朋友的Accord Coupe支撑性好的
不是一点点。雪地过弯很典型的understeer,一脚油门就向外,一松油门就回来。
然后是Fusion SE 2.5。也是S档手动换档。对这个车的变速箱我意见很大。明明是DCT
吧应该?cmiaw, 但是换档好慢,说实话我都等急了。。而且自动换档的时候有顿挫。
所以试完Fusion就直接出局了。但是这车也是有优点的。底盘比较适中,不那么硬,也
不像佳美那么绵。转向也不错而且不那么轻。座椅是个大亮点,我很喜欢那个感觉。
然后重头戏,Subaru Legacy。内饰感觉不很Techy,方向盘非常直接,刹车踏板感觉没
什... 阅读全帖
i****x
发帖数: 17565
37
来自主题: Automobile版 - Rx8还值得买么
我不知道你开过mx5没有,我以前开mx5现在开s2k,而且有一段是两辆车一起开,这两
个车可不是一个层面的东西。动力就不多说了,170 vs 240你知道的。悬挂s2k比miata
硬的多,turn-in的sharpness、body roll的控制、切入地面的感觉完全不能比,开过
s2k后再开miata觉得方向盘很松,车身很散,一转弯body roll大的不得了。另外s2k调
教几乎是完全的neutral,又有torsen lsd,而miata则是倾向于understeer,所以刚从
miata换成s2k时车尾甩出去很多次,就是因为miata过弯时即使push也总还是
understeer,后轮一旦开始打滑就失去动力了,而s2k是完全neutral的,大马力又有
torsen,猛踩油门马上甩尾。另外内饰和总体做工两车也不是一个级别的,老miata大
多有点漏油,门下面也容易锈蚀,而s2k内饰全皮,赛车座椅,HID头灯,我的十年老车
还跟全新一样。
S2k的发动机噪音远大于miata,但是路噪风燥隔音都比miata好。miata坐的很低,好像
坐在地上似的,s2k坐的其实不是特别低,应... 阅读全帖
c*********r
发帖数: 19468
38
我没说不行啊,但是有前提
在直道上你能从traction低的一侧向traction高的一侧转移扭矩
在弯道上,如果你要保证所有车轮都不打滑,那就只能从外侧向内侧转移扭矩,这和SH
-AWD这种TV系统是反的
SH-AWD(还有Evo的AYC/S-AYC、Audi的sport quattro后差、BMW X5/X6的DPC后差,等
等)可以减少understeer
eLSD在不打滑的情况下工作只能增加understeer……什么时候eLSD才能向外侧转移扭矩
?等内侧达到附着力极限开始打滑,转速赶上外侧之后,才有机会向外侧转移扭矩。
光百度一个数,一句话,贴过来,也不知道其中的道理,往往是没什么意义的……
p******r
发帖数: 1279
39
德车,日车,法拉利,且不说马力的比较,就同等马力的车来讲,什么车才算操控好?
一辆操控好的车,最主要的要素就是要predictable,也就是可预见性。好的车在车尾
后轮临界打滑的时候或者前轮推头的时候,会给车手足够的信息反馈,这个反馈是通过
多种形式表现的,比如方向盘的反馈,车体震动的反馈,车辆横向G力的反馈。 车什么
时候understeer?什么时候oversteer?避震弹簧和前后轮的damper对understeer和
oversteer有什么影响?什么叫重心转移?什么叫engine braking?engine braking会
不会导致车辆失控? 这些东西都不懂就过来谈论尼玛车辆操控,是用屁股在谈论吗?
什么日车操控完全比不上宝马,真正懂操控的人能说这样的话吗?不被内行笑掉大牙才
怪。。。
s*****8
发帖数: 606
40
You are "right" about one thing, driver uses 屁股 to feel if the car starts
oversteering.
damper is only one thing can affect understeering or oversteering. and most
important, driver is the key to induce understeering or oversteering.
Be polite, people here is talking about 操控 for fun. If you do know the
answers for what you quesitoned, please write it down (I bet you don't,
because we can tell from your novice questions)
Y****a
发帖数: 17170
41

你的感觉是对的。
AWD的车好像天然的就会更倾向于understeering。
Subaru几乎所有的车都是如此,尤其是给老人妇女开的车型,嘿嘿。
你说audi也如此,我一点都不觉得奇怪。
所以在subaru的社区,大家推荐做的第一项mod,就是加粗RSB,效果非常明显,
不仅可以修正这个问题,而且还可以增加稳定度。
但是厂商很少会去修正这个,为什么呢?
我想是因为understeering 比oversteering安全,你最多就是多打打方向,
但是oversteering一不小心就会引起各种失控。
我觉得forester 2.5的悬挂的绝对综合硬度和impreza差不多,parts都恨不得是通用的。
但是因为重心高,这个就显的感觉软了些。
上一代的forester确实是太灵活了,我自己也很受不了,
不过我也没有怎么大开14+的2.5i,所以也不好下结论。
颠于不颠,完全就看个人的反应了。
要是换我,我肯定不觉得颠,因为14FXT就已经比较硬了,现在又被我加固了一轮了。
嘿嘿
B*Z
发帖数: 7062
42
来自主题: Automobile版 - Accord V6 EXL报价、讨论及求建议
更稳是车头更重。车头重了understeer就更严重。但是你开直路,understeer帮助车稳
定。噪音小是因为同样速度,6缸车发动机转速低。

CVT
Y****a
发帖数: 17170
43
来自主题: Automobile版 - 你们OB都换rear Sway bar了么?

其实还是改善understeering的程度。
AWD的车天然会understeering,
subaru和audi都这样。
e******g
发帖数: 5344
44
legacy 6缸的四驱(5at的)没有阉割,全时45/55分配的,有机械中差,跟A4一个档次
的,平民车里面可以说是最好的公路四驱了。S60平时前后断开的,适时四驱的话只能
打滑后才有反应,legacy的是能预测打滑,而且rear bias的动力分配对减轻
understeer很有帮助。S60我当时有考虑过,但是understeer严重得让人没法忍,高速
下个弯道速度都必须很慢,要不车感觉要甩出去,最后没买了。
S60只有T5发动机,新的老的stock的动力都不比legacy 3.6,新发动机还只有前驱,除
了内饰好点,基本跟legacy没法比吧。。

壳吧
e*******l
发帖数: 1269
45
来自主题: Automobile版 - Mazda i-Active AWD
与CRV和森林人(配置CVT)的AWD作了实地比较。测试在美国科罗拉多州进行,包括雪
地障碍弯道和爬坡测试:
http://www.mazda-motors.com/news/mazda-ice-academy-trial-by-ice
下面是其中一位记者对比驾驶后的总结,其他记者的结论也大同小异
-- CX-5的i-Active AWD完胜森林人和CRV:
http://driving.ca/mazda/auto-news/news/mazdas-i-activ-awd-takes
A comparison between a couple of competing vehicles. Included are the
Honda CR-V and Subaru Forester, which join a CX-5 on a snow-covered slalom
course followed by a long, sweeping right turn. All vehicles are equipped
with Bridgestone Blizzak DM-V2 wi... 阅读全帖
d***a
发帖数: 13752
46
来自主题: Automobile版 - Mazda i-Active AWD

最大的亮点是轮胎。:) 版上有个别脑子不灵光的人,总以为AWD比FWD安全。其实AWD的
优势在于通过性,不是安全性。雪地下坡需要刹车的时候,同车型的AWD版反而更不容
易刹住。
Tires, Tires, Tires
To demonstrate this difference, Mazda provided an AWD CX-3 with standard
Yokohama all-season tires and one with factory recommended Bridgestone
Blizzak winter tires. Around a snow-covered track, the winter tire advantage
was stark. The car equipped with winter tires exhibited much less
understeer around corners, much better acceleration from a stop, and a much,
much shorter stopping dis... 阅读全帖
e*******l
发帖数: 1269
47
来自主题: Automobile版 - Mazda i-Active AWD
与CRV和森林人(配置CVT)的AWD作了实地比较。测试在美国科罗拉多州进行,包括雪
地障碍弯道和爬坡测试:
http://www.mazda-motors.com/news/mazda-ice-academy-trial-by-ice
下面是其中一位记者对比驾驶后的总结,其他记者的结论也大同小异
-- CX-5的i-Active AWD完胜森林人和CRV:
http://driving.ca/mazda/auto-news/news/mazdas-i-activ-awd-takes
A comparison between a couple of competing vehicles. Included are the
Honda CR-V and Subaru Forester, which join a CX-5 on a snow-covered slalom
course followed by a long, sweeping right turn. All vehicles are equipped
with Bridgestone Blizzak DM-V2 wi... 阅读全帖
d***a
发帖数: 13752
48
来自主题: Automobile版 - Mazda i-Active AWD

最大的亮点是轮胎。:) 版上有个别脑子不灵光的人,总以为AWD比FWD安全。其实AWD的
优势在于通过性,不是安全性。雪地下坡需要刹车的时候,同车型的AWD版反而更不容
易刹住。
Tires, Tires, Tires
To demonstrate this difference, Mazda provided an AWD CX-3 with standard
Yokohama all-season tires and one with factory recommended Bridgestone
Blizzak winter tires. Around a snow-covered track, the winter tire advantage
was stark. The car equipped with winter tires exhibited much less
understeer around corners, much better acceleration from a stop, and a much,
much shorter stopping dis... 阅读全帖
t********m
发帖数: 54
49
Buying TIPS is a perfect example of trusting the fox to guard your hen house
. The basic problem with TIPS is that they are indexed to the CPI, which
does not reflect actual inflation, but rather the government's highly
understated version of it. Ultimately, the CPI can be manipulated to produce
any result the government wants. As the supply of TIPS outstanding
continues to increase, so too does the government's incentive to make them
less costly by understating the CPI.
Peter Schiff, "Crash Pro
O*******e
发帖数: 1024
50
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codehacker (hh) 于 (Tue Aug 23 12:03:11 2011, 美东) 提到:
拿到intel的offer,还没开始上班,想请教intel办绿卡的政策?
thanks!
☆─────────────────────────────────────☆
codehacker (hh) 于 (Tue Aug 23 12:18:30 2011, 美东) 提到:
我是想知道办理的时程 例如加入后多久开始办理..
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begoing (eryday) 于 (Tue Aug 23 12:51:28 2011, 美东) 提到:
基本上没戏办EB1B,哪怕你有EB1A的背景,你可以自己尝试着办EB1A如果实力够强的话
只能等着办EB2,一般是加入公司两年后开办,再加上排期,估计还得等上个4~5年

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