One of the best features of turbocharged Macans, is how easy it is to increase power. Unlike naturally aspirated engines, turbocharged engines respond well to simple bolt-on modifications and even better to an ECU flash. Our Porsche Macan has a few bolt-on parts and an ECU tune, and the OEM diverter valves can no longer keep up with the demand.
The OEM diverter valves work fine at the stock power level, but they crack and leak boost when you increase power. Sometimes, the stock Borsch diverter valve will fail at the stock power level. In our case, the Macan was tapering boost levels at high RPM, resulting in less boost and less power. The solution is to ditch the stock diverter valves for a set of Agency Power diverter valves.
Diverter valves work by measuring pressure at the valve and comparing it to pressure in the intake manifold. Once the throttle body closes, pressure at the valve will increase and pressure inside the intake manifold will decrease. The different pressure levels will open the diverter valve, routing the excess boost pressure back into the air box.
Unlike the OEM Bosch diverter valves on our Macan, Agency Power constructs these valves from high quality CNC machined aluminum. Inside the aluminum housing is a much stronger diaphragm and spring which can adequately hold up to the boost pressure. After installing these diverter valves on our Macan GTS, boost stayed consistent throughout the RPM range. With the boost holding strong, the Agency Power diverter valves increased horsepower and improved throttle response.