Introducing the GFB SV45 - The latest and BIGGEST addition to our extensive range, designed specifically for drag racing and big horsepower engines.With a 45mm piston and three large flared outlets, the SV45 flows like nothing else!Key features:•  Capable of supporting in excess of 1000hp!•  Massive 45mm piston, with smooth flow contouring. •  Three flared venting ports cut into the body with a dual angle, designed to match the piston at full travel for the smoothest flow path of ANY valve on the market. •  Tapered Acetal piston seat for a perfect seal under boost.•  Unique ball-type attachment method for a fast, easy and reliable installation. •  Comes with two springs to suit all engine types. •  Aluminium weld-on adaptor supplied, stainless steel also available (part # 6408)