TBM Brakes Brake Calculator
There are 3 key components to effective pressure delivery to your calipers in order to have adequate braking performance potential at the caliper. Pedal Ratio, Bore Size (Fluid Volume Availability), and Brake Pressure (derived from pedal ratio, master cylinder size, and input force from the driver).
Below are calculators to help you plan a proper brake setup.
*Note: these calculators do not take into account or verify that your caliper style/design, pad compound or rotor size are adequate to achieve your goals*
Calculate Pedal Ratio
*Factory Pedal Ratios on vehicles equipped with power brakes are typically 4:1. For manual brake conversions we typically target between 6:1 or 7:1. Note, different length pushrod and master cylinder placement may need to change to accommodate.
Note: making sure your master cylinder pushrod does not have preload at neutral is important to proper system function. Watch this video to learn more: Click Here
Calculate Master Cylinder Area (sq. in.)
Calculate Effective Pressure at your Master Cylinder
*We recommend a normal operating pressure of 7-800 psi*
*Recommended max achievable pressure of 1200psi*
*Typical input force is 100pounds by average weight and size driver. Input force can vary from 70 lbs to 150+ depending on driver. See This Video (link) to understand how to calculate this.
Calculate Master Cylinder and Pedal Travel
*Note: for reference a larger master diameter results in a harder feeling pedal with less travel, this allows for less modulation of pedal feel for driver.*
*Note: smaller bore master cylinder results in softer feeling pedal with more modulation but a longer pedal throw to achieve pressure*
Calculate Master Cylinder Fluid Output (Cu. In.)
*Note compare this to your fluid requirement to determine adequate fluid volume is available for your braking demands. Output needs to be greater than requirement below*
Fluid Requirement By Your Brake System
*Note: if you have varying size pistons, it may require you to do this calculation for each caliper separately and add the results together for overall Fluid Requirement*
*Note: pad movement may change depending on style of caliper and system being used. Typically this number can be between .01 and .03 after a system is bled, consult your brake manufacturer if needed* For reference, piston size and quantity are here for our drag racing calipers. Many aftermarket calipers run different sizes pistons, consult your manufacturer.
DR1: (2 pistons: 1.75" Diameter)
F1: (2 pistons: 1.75" Diameter)
F3: (4 pistons: 1.75" Diameter)