The ALTA MINI Cooper S and JCW (2007+) Hot Side boost tube replacement replaces the restrictive OEM rubber hoses with a larger diameter and smoother 5-ply silicone hose. At the same time, this removes a restrictive intake muffer which combined to increase power roughly 5HP at the wheels. The ultra smooth interior surfaces of the ALTA Boost Tube combined with the removal of the restrictive intake muffler allows your turbo to run more efficiently. In turn this means better response and more horsepower! This part goes great with the ALTA larger front mounted intercooler. Together you will see 15-20 Wheel horsepower gains!