Hey, I'm currently building a single seater racer as a college project.

I'm using a 600cc motorbike engine and it weighs 300kgs. I am currently designing the Braking System of the car. I am restricted in using a single caliper mounted to the differential at the rear.
I am trying to design a pedal box to house the brake pedal but i'm having trouble figuring out how to determine the distance between the push rods of the Master Cylinders, to achieve correct set up.

Most of the components have been purchased from previous years projects, I have no choice on them unless I can make a strong argument against them.

I have worked out the Pedal Ratio is 3.454
The two master cylinders Front + Rear bore diameter 0.442 and 0.75 inches.
Two pot calipers all round 1.6141 inch Piston , Two on the front and one on the back axle. (Calipers tested to 1000 Psi)
The car weighs 300 Kg (120kg front, 180kg rear)

Ive made an excel spreadsheet with some of the major calculations:

I calculated the torque needed ( front 1103 Nm , rear 393 Nm)

With a 50/50 split in the balance bar + 30Kg leg input,
i'm getting a line pressure of

( front: 744.66 Psi , Rear : 258.63 Psi )

I have calculated a disk torque achievable
( front 1,407 Nm , rear 244 Nm )

What do you think of my figures?
Can / Should the balance bar be used to give greater pressure to the rear?
Are the line Pressures too high?

Any advice information or criticism is welcomed and would be greatfully appreciated.

Thanks, Gerard

Assuming all your calculations are correct it would still be advisable to put some form of bias bar on due to the weight, or lack of it. If you have a 50/50 brake distribution you will find that the rears lock up before the front, for an MOT as an example, you need 70%+ brake force at the front.

Sorry! I never made such calculations. No idea. Your post looks good.


SuperChargers