Oversteer & Understeer

[ian_rex]

please forgive my stupid notion, i can't help it.

been driving for sometime now (almost a decade) and have many experience on the road. being a motorhead, i love speeds as many drivers do. however, i decided to take my technical knowledge of driving another step. that is, i just wonder what is the difference of oversteer and understeer? sometimes i'm confused of the two terms. though, i think i can handle both when need arouse, i still need to know the difference of the two.

i would certainly appreciate your inputs. thanks in advance.

[benchph1]

front wheel drive cars (mostly)understeer

some people call it going "wide". its the behavior or front wheel drive cars when nearing their traction limit. its the feeling when going in a corner your turning right for example, feet planted in the accelerator. you thought you're going right but the car is swerving to the left.

rear wheel drive cars (mostly) oversteer

because the drive wheels is at the rear, when they approach the traction limit their rear ends tend to sway to the direction intended by the driver. now this is the dangerous but exciting "drift" comes from. :D

[kimpOy]

from progressauto.com

[ian_rex]

ok thanks sir. may nakakatakot nga ang mga rear wheel drive na cars, mas madalas mag 'tail-out' or tail-wag lalo kapag high speed cornering.

teka, nalito ako a. correct me if i'm wrong, mas nag-a-underrsteer ang rwd kesa fwd tama?

[jim]

mas nakakaakot ang rwd kesa fwd??? in any case mas advantageous ang rwd system kesa fwd system kasi sa rwd walang masyadong strain sa front wheels and its components dahil yung traction nasa likod unlike sa fwd traction, steering lahat nasa harap. sa hi-speed cornering mas maganda ang rwd kesa fwd dahil wala ngang masyadong strain sa front wheels. oversteer and understeer can both happen in fwd and rwd vehicles kaya katakot-takot ang ginagawang mods sa steering at suspension para maiwasan ito although oversteer is advantageous in racing.

[kimpOy]

advantage ang RWD,

imagine this ano ang mas bilis at mas may control
Pulling a cariton or Pushing it?

[jim]

precisely sir kimpoy. natumbok mo hehehehehe

[ebbfolls]

advantage ang RWD,

imagine this ano ang mas bilis at mas may control
Pulling a cariton or Pushing it?

Sir,

Wala hong bearing kung 'pushing' o 'pulling' yung driving wheels [In fact, it is widely known that drivers in colder climates benefit from fwd ('pulling') because the engine weight resting on the driving wheels help significantly with the traction in the snow]. Ang importante po sa acceleration ay 'Available Traction'. At dahil nga me tinatawag na 'rearward weight transfer' pag nag-accelerate ang isang bagay, mas malakas ang 'normal force' dun sa gulong sa likod kesa dun sa harap. Ang resulta, mas malakas ang hawak ng traction dun sa likod kaya mas mabilis makapag-accelerate ang rear wheel drive.

Tungkol naman sa handling, mas madali i-correct ang understeer kesa oversteer. Dahil dito, karamihan ng family cars ngayon ay fwd dahil mas madali itong mag understeer. Ang dahilan kung bakit mas-safe ang understeer ay nasa natural reaction ng driver pag nag-slide ang kotse--throttle lift off. Pag nag liftoff ka sa oversteer, lalo kang magkaproblema dun kasi wala na ngang traction yung rear axle, tinanggalan pa ito ng 'normal force' dahil sa braking effect. Sa makatuwid, you aggravate an oversteer condition by doing what one instinctively does in an emergency situation, i.e., you lift off the throttle. (The most prevalent reason for using fwd, however, is that it is more space efficient than rwd).

Sports cars on the other hand, are usually driven by people who know what they're doing. So in the event of an oversteer (which rwd cars are more prone to do), the driver can either countersteer in time or he will continue power while countersteering at the same time, effectively correcting the oversteer condition. Another advantage of rwd is that a seasoned driver can also control the amount of oversteer with the gas pedal as he guides the car around a corner.

[jim]

Sir,
[In fact, it is widely known that drivers in colder climates benefit from fwd ('pulling') because the engine weight resting on the driving wheels help significantly with the traction in the snow]. Ang importante po sa acceleration ay 'Available Traction'. At dahil nga me tinatawag na 'rearward weight transfer' pag nag-accelerate ang isang bagay, mas malakas ang 'normal force' dun sa gulong sa likod kesa dun sa harap. Ang resulta, mas malakas ang hawak ng traction dun sa likod kaya mas mabilis makapag-accelerate ang rear wheel drive.

may bearing pa rin sir from what you shared hehehehehe

[ebbfolls]

may bearing pa rin sir from what you shared hehehehehe

Actually, no Sir. Because it was not whether the tires were 'pullling' or 'pushing' but rather if the engine was sitting on top of the driving wheels. The fwd pulling better on the snow was because the engine was in the front. The same effect could have been achieved in an RWD if the engine was also sitting in the rear--like in the classic Beetle, or Porsche 911.