The High Strength Oversized stud kit eliminates the need for doweling the engine block. All studs act as dowels which massively increases torsionial strength 70%. Rotor housing deflection reduced - increases apex seal life. Less material machined from housings and plates than with doweling, reducing the possibility of cracking. High boost engine expansion reduced. Studs are less prone to stretching under high boost applications. More accurate tensioning of engine. Less chance of bolt breakage. High quality 12-point nuts rated at 180,000 PSI tensile strength. Studs manufactured from 4140 chrome moly, heat treated, centreless ground and black oxided. Engine must be accurately drilled, reamed and tapped to give 0.2mm clearance. Includes 16 studs, nuts and sealing washers. Does NOT include/need the two at the bottom of the "legs" closest to the oil pan.