الموضوع: كل شىء عن تعديل السيارات .A to Z.المادىء و النظريات العلميه.(منقول)

There has always been a huge debate over what to do if your car oversteers or understeers. The first thing people go to is always the swaybar when someone always asks how to "loosen" or "tighten" their car. However, there is a lot more to making your car handle to your liking, and everything will do a little something different depending on speed, turn-in rate, braking percentage, weight distribution and a number of other factors. To help everyone out, here is a list of things you can do to your car to get it how you want. You might even want to print it out and bring it to the track with you. Here goes:

TO REDUCE UNDERSTEER or INCREASE OVERSTEER:

Front tires:
- Increase tire pressure in 2.5psi increments
- Increase Section Width
- Lower the Aspect Ratio
- Reduce front tread depth

Rear Tires:
- Reduce tire pressure in 2.5psi increments
- Reduce section width
- Install higher aspect ratio tires
- Increase rear tread depth

Front Wheels:
- Install wider wheels
- Install lighter wheels

Rear Wheels:
- Install narrower wheels
- Install heavier wheels

Front Alignment settings:
- Dial in more negative camber
- Dial in More toe-out
- Dial in more positive caster

Rear Alignment settings:
- Dial in more positive camber
- Dial in more toe-out (Same as front)

Anti-Sway bars:
- Soften the Front
- Stiffen the Rear

Spring rates:
- Soften the Front
- Stiffen the Rear

Shock absorbers:
- Soften the Front
- Stiffen the Rear

Suspension Bushings:
- Soften the Front
- Stiffen the Rear

Brake Proportioning
- Reduce Front brake pressure
- Increase rear pressure

Weight Distribution
- Reduce front weight
- Increase rear weight

Aerodynamics:
- Increase Front Downforce
- Reduce rear downforce

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TO REDUCE OVERSTEER or INCREASE UNDERSTEER:

Front tires:
- Decrease tire pressure in 2.5psi increments
- Decrease Section Width
- Install higher Aspect Ratio tires
- Increase front tread depth

Rear Tires:
- Increase tire pressure in 2.5psi increments
- Increase section width
- Reduce aspect ratio
- Decrease rear tread depth

Front Wheels:
- Install narrower wheels
- Install heavier wheels

Rear Wheels:
- Install wider wheels
- Install lighter wheels

Front Alignment settings:
- Dial in less negative camber
- Dial in less toe-out (to toe-in if needed)
- Dial in less positive caster

Rear Alignment settings:
- Dial in less positive camber
- Dial in less toe-out (Same as front)

Anti-Sway bars:
- Stiffen the Front
- Soften the Rear

Spring rates:
- Stiffen the Front
- Soften the Rear

Shock absorbers:
- Stiffen the Front
- Soften the Rear

Suspension Bushings:
- Stiffen the Front
- Soften the Rear

Brake Proportioning
- Increase Front brake pressure
- Reduce rear brake pressure

Weight Distribution
- Increase front weight
- Decrease rear weight

Aerodynamics:
- Reduce Front Downforce
- Increase rear downforce



Well there you go. Keep in mind that any adjustment you do will affect the car so do not do more than 2 adjustments at one time. If those don't work or you still want more, keep trying but don;t do to many adjustments at one time. Any question, feel free to ask

المصدر:Make your car handle how you like it! - NASIOC

معلش يا رجاله بس معرفتش اترجمه لان فيه بعض المصطلحات مش معناها بالعربى ممكن فورميولاتور يدخل يوضح و يترجم و يفهم اكتر و يسهل المعلومه للاعضاء.
بس بصراحه مقاله مفيده جدا جدا جدا .