Angry Ass | S38 Vacuum Supply | Brake Booster
The S38B36 & B38 use ports on the throttle bodies of cylinder #5 and #6 to provide vacuum assist to the brake booster, via two lines feeding into a non return valve to the booster. These typically go unnoticed when hunting for vacuum leaks or chasing a hard brake pedal, but with these lines being tucked up next to the cylinder head and fire wall, they take on quite a bit of heat and abuse.
To make things easier and eliminate the guess work, we’ve assembled a complete kit of OEM components that allows you to tackle this oft-ignored problem, preventively or otherwise.
Additional Information
Assembled from OEM BMW lines and fittings
Clamps are both 304 stainless steel and made in the USA
The correct hardware type per BMW is an ear-style hose clamp, clamped with proper pinch pliers, but we have found it’s almost impossible to seal the hoses to the ports due to a lack of space (with the fuel injector harness rail in place). Due to this issue and wanting to avoid the risk of breaking the injector harness rail, or having to remove the entire throttle body set, we offer worm gear style hose clamps that you can tighten with a flat blade screw driver (or ideally a flexible 7mm nut driver such as Wera part number 391). The proper tool for installing the ear style hose clamps is Oetiker part number 14100498, if your car is further apart or you’re going for the Concours.
