Roush Performance has just outdone itself with a new Phase 2 supercharger kit for 2015 and later Ford Mustang GTs, bumping engine output up to a peak 727 horsepower from the 670 offered by the Phase 1 supercharger kit.
At the core is Roush’s latest 2.3-liter roots-type supercharger which, according to The Mustang News, utilizes twin four-lobe rotors with a 160-degree twist. Older units used three-lobe rotors with just 60-degrees of twist. Combined with revised a revised inlet and outlet, the supercharger is claimed to provide improved airflow, thermal efficiency, and operating speeds, with greater volumetric capacity, and reduced noise and vibration.
Granted, the same four-lobe, 2.3-liter unit already serves in the Phase 1 supercharger kit; the difference is in the additional equipment and calibration. A big, 60mm dual-bore throttle body is included, along with a fuel pump booster, Roush-designed high-flow injectors, new spark plugs, and an optimized ECU tune. The kit also provides a low-temp radiator, aluminum intercooler, high-capacity degas bottle (part of the cooling system), and a low-restriction air filter and induction system.
All-in, the new Phase 2 supercharger kit from Roush Performance costs $7,549.99 – up from $6,895.00 for the Phase 1 kit. Owners of the Phase 1 supercharger kit can purchase the handful of revised parts needed to take it up to Phase 2 $1,099.99.