BMW / MINI B38 ARP Head Stud Kit – ARP2000 & Custom Age 625+ Options The BMW and MINI B38 turbocharged three-cylinder engine is compact and powerful, but when boost and horsepower levels climb, the factory head bolts can quickly become a weak link. Under high cylinder pressures, stock bolts stretch, allowing the head to lift and leading to blown head gaskets or engine failure. The 5150 AutoSport ARP Head Stud Kit solves this problem with race-proven strength and durability, giving your B38 engine the clamping force it needs for both street and high-performance builds. Kit Options: ARP2000 (190 ksi tensile strength): Significantly stronger than OEM bolts, ideal for most tuned and high-boost B38 builds. ARP Custom Age 625+ (260 ksi tensile strength): The ultimate choice for extreme power levels and big-turbo setups, offering maximum reliability under the harshest conditions. Key Benefits for BMW B38 Engines: Prevents head lift and gasket failure under boost Stronger and reusable compared to OEM bolts Trusted by engine builders worldwide for high-horsepower applications Available in ARP2000 and Custom Age 625+ for different power goals Installation Instructions: 1. To ensure proper thread engagement and accurate torque readings, clean ALL threads in the block. Chase if necessary with ARP Thread Chaser. 2. Clean and inspect all hardware prior to installation. Look for obvious defects or shipping damages, plus proper fit, length and dimension. 3. If the cylinder head studs protrude into a water jacket, lubricate the block threads of the studs with ARP THREAD SEALER. 4. Screw studs into the block “HAND TIGHT ONLY”. 5. Install the cylinder head(s) and check for binding or misalignment. 6. Lubricate the stud threads, nuts and washers with ARP ULTRA-TORQUE FASTENER ASSEMBLY LUBRICANT. Then install the washers and the nuts onto the studs and tighten them hand tight. ARP recommends using the ARP ULTRA-TORQUE FASTENER ASSEMBLY LUBRICANT that is provided with each kit as opposed to motor oil. This is due to higher friction on the studs as well as inconsistencies in the clamping force of the fasteners when motor oil or other low quality lubricants are used. Please note: After initial assembly, it is necessary to allow the engine to complete a full heat cycle, then re-torque your head studs to spec. This means allowing the engine to warm up to its normal operating temperature, remain at operating temperature for several minutes to ensure each component is uniformly heated, then turned off and cooled completely to ambient temperature. PRELOAD (TORQUE) RECOMMENDATIONS 7. Following the manufacturers recommended torque sequence tighten the nuts steps 1-3 ARP2000 Step 1: Tighten to 30 ft-lbs. Step 2: Tighten to 60 ft-lbs. Step 3: Tighten to 90 ft-lbs. Custom Age 625+ Step 1: Tighten to 30 ft-lbs. Step 2: Tighten to 60 ft-lbs. Step 3: Tighten to 110 ft-lbs. with ARP Ultra-Torque fastener assembly lubricant Bolt Torque Sequence 6 1 3 7 8 4 2 5
