The BMW Toyota B58 Head Stud Thread Insert Kit provides your machine shop everything needed to repair or upgrade the engine block threads on BMW Toyota B58 engines. Designed for precision and durability, this kit allows you to restore damaged threads or prepare the block for oversized head studs for improved clamping strength.
Please note, this product does NOT include head studs. Head Studs are available for purchase here.
Each BMW Toyota B58 Head Stud Thread Insert Kit includes:
- (1) Specialized drill bit for proper thread preparation
- (1) High Speed Steel 3-Flute Tap
- (1) High Speed Steel Extended 3-Flute Tap
- (14) Precision stainless-steel thread inserts
- Red threadlocker
Available in 11mm for OEM-spec head stud thread repair or 12mm for use with our Oversized Head Stud Kit , this thread insert kit ensures a secure and permanent repair capable of withstanding extreme cylinder pressure and torque loads.
How these inserts work:
Our insert design supports the use of both factory head bolts and high-quality aftermarket ARP head studs. These fasteners use rolled threads, which are up to 20% stronger than cut threads, and are engineered to flex and return to shape as the engine heats and cools—maintaining consistent clamping pressure on the head gasket throughout every heat cycle.
Benefits of Installing Oversized Head Studs:
- Repair Worn or Damaged Threads
When an engine block’s head bolt holes become stripped or elongated from repeated torque cycles or overheating, a standard-size stud may no longer hold properly.
By drilling and re-tapping the holes to a larger diameter and using oversized studs, you restore proper thread engagement and strength—often stronger than original.
- Increase Clamping Force
Oversized studs can have a larger shank diameter, which increases tensile strength and reduces stretch under high cylinder pressures. This is particularly beneficial for high-boost turbo where combustion pressures are extreme.
- Reduce Head Gasket Failure
Stronger or larger studs provide more uniform clamping across the cylinder head, which improves gasket sealing and minimizes the risk of head lift or gasket blowout.
Not all engine blocks are suitable for oversize head stud installation. Due to differences in casting thickness, core shift, and material distribution, some blocks may not have enough surrounding material to be safely machined for larger fasteners.
A skilled and experienced machinist must inspect the block and be confident in its integrity before performing any machining. Improper assessment or installation may result in cracking, coolant passage intrusion, or structural failure. All modifications are performed at the installer’s own risk.
Please Note: Installing oversized head studs requires precise machining; drilling and tapping the block must be completely straight and to the correct depth.
Don't have a machine shop capable of the job? Send your block to 5150 for our oversized head stud installation service.
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