M52TU/M54 12mm Head Stud & Gasket Kit
SLG 12mm Head Stud Conversion Kit for BMW M52TU/M54 Engines
The ultimate head clamping solution for the aluminum block M52TU and M54 engines. At high power levels, the factory 10mm head bolt/stud setup can become a limiting factor. On our own time-attack car, we ran into head lift during track sessions where the engine was exposed to high cylinder pressure, high coolant temps, and extended abuse. Even upgraded 10mm studs with Time-Serts were not enough for what we needed to keep the engine reliable.
So we built a real solution.
This SLG kit converts the engine to specialty 12mm ARP 2000 head studs that are not available in any off-the-shelf kit. The larger stud provides a massive increase in clamping capability and is designed for serious high-power, high-heat, and motorsport use. The threads are also huge, so no need for any Time-Serts, these achieve the same thing.
The kit includes a reamed Cometic head gasket in your choice of thickness, modified specifically to accept the 12mm studs. It also includes ARP 2000 head studs, specialty washers designed to fit the factory head pads, and narrow nuts that allow use of a large 14mm 12-point socket between the valve springs.
Yes, this kit is expensive — but these are special-order ARP parts, and the head gasket requires specialty machining. The benefit is that this setup does not require Time-Serts, saving the cost of the insert kit, tooling, and installation process required to properly install them.
Since moving to this 12mm stud setup, we have not had any head lift issues.
Machining Requirements:
- The cylinder head must be drilled to 12.5mm for stud clearance. No dowels used.
- The engine block must be rethreaded and counterbored to accept the 12mm studs.
- This is a straightforward machining operation for any qualified machine shop familiar with performance engine work.
Torque Recommendation:
Our recommended final torque value is 95 ft-lbs.
Recommended torque sequence:
- 45 ft-lbs
- 75 ft-lbs
- 95 ft-lbs
In our experience, the studs can be torqued up to 110 ft-lbs if needed for extreme applications. At that point, the limiting factor becomes block distortion and water jacket cracking before the studs become the weak point. These studs mean business.
Lead Time:
Please allow approximately one week for head gasket machining.
