Suits the AP Racing Lockheed Caliper CP4226 & CP4227

Formula Student CP4226 & CP4227 Brake Pads

The most commonly used calipers is Formula Student are CP4226 and CP4227, these both use CP4226D27 brake pads. These pads are available in the following compounds:

All of these pads for the CP4226 and CP4227 calipers have a total thickness of 27mm and the compound material is 7mm thick.

The APH420 compound will allow the driver to be more progressive on the brakes (allowing for smoother cornering speed). The RX compound will give a more aggressive stopping power allowing the car to stop in a shorter space. The RQ3 is a compromise between these two options.

Because these pads are normally used in motorcylces they are supplied in a pack of 2 pads.

Brake Pad Part Numbers

Brake pads part numbers are split into two sections. The first is the shape number, this tells us what the shape, size and (sometimes) thickness. Different pad manufacturers have different ways of laying out this section of the part number. This is important so that we know the pad will actually fit into the caliper. The second part of the part number tells us the compound. The compound is the material which makes contact with the disc. Different materials have different properties, some will stop the car quicker but may not allow for a more progressive speed reduction of the car.

Brake Compounds

Commonly we will look at several properties of the compound:

• Coefficient of Friction - This is the ratio of the frictional force between two surfaces. a value of 0.00 means that the two surfaces will not make an impact on each other, a value of 1.00 means that the surface which is moving will stop suddenly
• Longevity of the pad - How long the pad will last. For endurance racing we will prefer a pad that lasts longer, but this will often not be as agressive. The thickness of the pad also factors into this
• Temperature - The material will have it's best performance at a set temperature range, in most other forms of motorsport we will do a lot of research to find what temperature the brake pads are getting to (this is usually determined by the speed (energy) and weight (mass) of the vehicle