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SAAB Automobile ABis a car manufacturer within General Motors corporate group. SAABAutomobile ABhas a big part of the responsibility for the brake development in the corporategroup. The car industry is facing harder environmental requirements, which influence the brakedevelopment. The focus is to develop brakes with low drag and sustained brake feeling andperformance. Important characters for the brake caliper are high stiffness and low weight, highstiffness results in high performance and low weight is important because it is unsprung mass.This thesis investigates the possibility to improve the performance of the brake caliper for aGMproject. The aim is to design a caliper with less amount of material but with the same stiffness.The delimitations are that the manufacturing costs should be unchanged and the design shouldwork without modifications of the surrounding parts.Computer aided design models (CAD- models) are built inSolid Edge, which are evaluated withfinite element analysis (FEA) inAnsys Workbench. An organized design of experiments is usedto find the optimal geometry of the caliper. A free form fabrication model of the concept is builtwhich are used as a probe when moulding a cast iron prototype of the concept. Two types ofpractical tests to measure the stiffness in brake calipers are evaluated. One test where thedisplaced amount of brake fluid is measured and one test where the deformation is measuredwith dial indicators.The results from the FEA show that the concept has a weight of about 3.2 kg, compared to theweight of the original caliper at about 3.6 kg. The stiffness in the concept is about the same asthe original, even marginally better. The stress in the concept is more evenly distributed whichindicates a better use of the material.The stiffness in the prototype does not reach the same levels as the original caliper according tothe practical tests. Possible reasons are the small scale production and insecurity of the materialproperties. The methods to evaluate the stiffness in the calipers are working properly and seem tobe good methods for practical evaluation of stiffness in calipers.