How Much Force to Fully Depress Car Brake Pedal?

In summary, the amount of force required to fully depress a car brake pedal depends on the car's brake system, with an average mechanical advantage of 3:1 to 6:1 for non-power brakes and 8:1 for power brakes. A typical formula car with a master cylinder bore of .750" and piston area of .442 sq. inch can generate 2396 pounds of force on individual discs with 150 pounds of force applied to the piston. If the brake pedal can be fully depressed, there may be issues with worn pads or air in the brake lines. To calculate the actual energy required to decelerate a race car, the formula is 0.0335 x (maximum MPH squared - minimum MPH squared
  • #1
sefo21
1
0
I have a simply question: how much force must be applied to an average car brake in order to fully depress the pedal?
Also, if you know the answer, do you know where I could substantiate it?
Thanks for any help you can offer.
 
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  • #2
It obviously depends on the car, if you just want a rough answer you can measure it.
Either hook a fishing scale type spring balance under the pedal and then press down (preferably while not in traffic) or remember how much effort you had to push with and then try and push your foot down on a bathroom scale with the same force and see what it reads.
 
  • #3
assume you have disc bakes on all corners..there is a brake pedal with actuator arm to master cylinder. usually master cylinder has two reservoirs..in old days only one was used..the front cylinder is larger than the rear as the engine weight is on front end. more weight means more braking requirement. stainless steel brake lines 3/16 to 1/8 inch diameter take brake fluid to each wheel caliper ( piston and mounting arrangement.) the brake disc is fitted to the axle and when force is applied to the master cylinder..pressure acts on pistons pushing brake pads to contact the rotating wheels discs..


typical mechanical advantage of the brake pedal to master cylinder is 3:1 and 6:1 ( non power brake set up) power brake mech. advantage is 8:1
our formula car has master cylinder bore of .750" with piston area of .442 sq. inch, makes line pressure with 150 pounds force on piston 339 psi
pedal travel to move pads 0.010 inch .96 inch ( 4 Pot caliper with 1.50" pistons) generating applied force to individual discs = 2396 pounds

if you are able to completely depress the brake pedal you have problems..you should be able to depress the pedal about 1/2 inch until you get a firm brake pedal..if not, you pads are too worn or you have air in the brake lines and must ' bleed" the brakes..i.e. pump up pedal and hold it until you buddy cracks the bleeder and permits trapped air to escape..
lot of other stuff I can tell you but let me know is this is sufficient
 
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  • #4
actual energy required to decelerate a race car
energy (lb./ft) = 0.0335 x { MPH Max ) squared ( mph min) squared } x gross weight
1760 lb. car braking from 150 mph to 60 mph would take 1,114,344 lb./ft.
and there is MUCHO heat...
 
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Related to How Much Force to Fully Depress Car Brake Pedal?

1. How much force is needed to fully depress a car brake pedal?

The amount of force required to fully depress a car brake pedal varies depending on the type of car, the condition of the brakes, and the weight of the vehicle. Generally, it takes around 25 to 35 pounds of force to fully depress a brake pedal.

2. Can the amount of force needed to fully depress a car brake pedal change over time?

Yes, the amount of force needed to fully depress a car brake pedal can change over time. Factors such as wear and tear on the brakes, changes in the weight of the vehicle, and changes in the condition of the brake system can all affect the amount of force required.

3. Is it possible to fully depress a car brake pedal with less force?

In most cases, it is not recommended to try to fully depress a car brake pedal with less force. The amount of force required is designed to provide optimal braking performance and ensure the safety of the driver and passengers. Trying to use less force can result in reduced braking power and potentially lead to accidents.

4. What happens if you apply too much force to a car brake pedal?

If too much force is applied to a car brake pedal, it can cause the brakes to lock up and the wheels to skid. This can result in loss of control of the vehicle and potentially lead to an accident. It is important to apply the correct amount of force to the brake pedal to avoid such situations.

5. How can I determine the amount of force needed to fully depress my car's brake pedal?

The best way to determine the amount of force needed to fully depress your car's brake pedal is to refer to the manufacturer's recommendations. This information can usually be found in the owner's manual or by contacting the dealership. Additionally, you can test the force required by gradually applying pressure to the brake pedal while the car is stationary.

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