The ARP 201-4305 Cylinder Head Stud Kit is engineered for BMW's M20 2.5L 6-cylinder engines, specifically the 1985–1991 E30 325i, 325is, 325iX, and the 1989–1990 E34 525i. This kit replaces the factory head bolts with high-performance ARP studs, providing superior clamping force and improved sealing under high boost or high compression conditions.
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