This ARP2000 Head Stud Kit 203-4705 is designed for the turbocharged inline 6-cylinder B58 engines found in varias BMW chassis and the Toyota GR Supra A90/A91. As you increase the power output of your engine beyond its factory specifications, the head and block may start to separate, causing factory bolts to stretch and fail. ARP Head Studs are stronger than factory bolts, ensuring your race engine stays together even under extreme conditions.

The Custom Age 625+ option203-4706is made from ARP’s 625+material that has a tensile strength of260 ksi, substantially higher than the 190 ksi of the ARP 2000 head stud. It’s an ideal choice for individuals who want to push the limits of their B58builds and require a stronger head stud.

Our Oversized Kit option utilizes ARP’s proprietary Custom Age 625+ material option combined with specialized insert washers for ultra-high boost applications. Please note that this kit requires that the cylinder head be clearanced and the engine block to be machined for the installation of insert washers. Don’t have a machine shop up to the job? Submit your engine to 5150 AutoSport for our B58 Oversized Stud Installation Service.

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
ARP2000Step 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.
Oversized Custom Age 625+Step 1: Tighten to 50 ft-lbs.Step 2: Tighten to 90 ft-lbs.Step 3: Tighten to 130 ft-lbs.
with ARP Ultra-Torque fastener assembly lubricant
Bolt Torque Sequence

BMW B58 Gen 1 Applications:

1 Series

2016-2019 F20/F21 M140i

2 Series

2016-2019 F22/F23 M240i

3 Series

2015-2019 F30/F31 340i / 340i xDrive
2016-2019 F34 340i GT / 340i GT xDrive

4 Series

2016-2020 F32/F33/F36 440i / 440i xDrive

5 Series

2016-2019 G30/G31 540i / 540i xDrive

6 Series

2017-2019 G32 640i GT / 640i GT xDrive

7 Series

2015-2019 G11/G12 740i / 740i xDrive

X3 Series

2017-2019 G01 X3 M40i

X4 Series

2018-2019 G02 X4 M40i

BMW B58 Gen 2 Applications:

3 Series

2019-Present G20/G21 M340i / M340i xDrive

4 Series

2020-Present G22/G23/G26 M440i / M440i xDrive

Z Series

2019-Present G29 Z4 M40i

5 Series

2020-Present G30/G31 LCI 540i / 540i xDrive

6 Series

2020-Present G32 LCI 640i GT / GT 640i xDrive

7 Series

2019-Present G11/G12 LCI 740i / 740i xDrive

X3 Series

2020-Present G01 X3 M40i

X4 Series

2020-Present G02 X4 M40i

X5 Series

2018-Present G05 X5 xDrive40i

X6 Series

2019-Present G06 X6 xDrive40i

X7 Series

2018-Present G07 X7 xDrive40i

ALPINA B58 Gen 2 Applications:

B3 Series

2020-Present G20/G21 B3

B4 Series

2022-Present G22 B4

B5 Series

2020-Present G30 B5

XB7 Series

2020-Present G07 XB7

Toyota B58 Gen 2 Applications:

A90 / A91 Supra

2020-Present GR Supra 3.0
2020-Present GR Supra 3.0 Premium
2021-Present GR Supra 3.0 A91 Edition