S13 Wisefab knuckle has revised kinematics when compared with OEM and built in anti-squat

There are no springs

\n2 x 1/8 NPT Hose Tail Fittings

never exceeds the manufacturers tolerances - This will provide you rock solid oil supply pressure

BOV ProPort GenV Supercharger Black Touch Up Paint S13 Wisefab knuckle has revisedProPort by Turbosmart is an All New 54mm (2. 13in) Blow Off Valve with a tiny footprint and massive flow. The ProPort flows 420 cfm which is enough for 3500 HP and is in a league of its own standing 30mm (1. 2in) lower than PowerPort while flowing over 25% more than the Market leading 50mm Raceport. Features include our unique locking collar design, new unique vent profile, sensor cap option and spring options for all turbocharged and supercharged