Abstract: A spacer secured to a dash panel offsets a boost unit of a brake system into an engine compartment. The spacer has a cylindrical body with a u-shaped space through which air from the engine compartment is communicated to the boost unit to effect a brake application. The u-shaped space is divided by a plurality of walls into first and second labyrinth paths around the cylindrical body. An open cell gasket is located between the boost unit and the spacer to seal the u-shaped space. Air enters the u-shaped space and is divided into equal volumes that flow around the cylindrical body to a radial opening in the cylindrical body for distribution to the boost unit. Air flowing along the first and second labyrinth paths encounters the open cell gasket and sounds generated in the engine compartment are attenuated by being absorbed prior to delivery to the boost unit.

Abstract: A fixture and technique for testing a coil spring selected from a supply of springs. Each spring has an unstressed generally helical configuration and the test determines an excess departure from the helical configuration of a spring under a compressive load. The first end of a selected spring is radially fixed in a first guide while a second end of the spring end is axially retained in a movable second guide that is supported on rollers to allow omni-directional transverse radial motion of the second end. An axial compressive force is applied to the selected spring while allowing the second end relatively free radial motion. When compression induced radial motion of the second end exceeds a predetermined threshold, the second end the selected spring closes a normally opened electrical circuit to inform an operator that the selected spring is excessively out of square and should be rejected.