5150 AutoSport Head Gasket & Head Stud Kit, BMW M20

MLS Head Gasket:

This Cometic MLS Head Gasket is specifically engineered to replace BMW part #11121722734, 11121722735, 11121722737, and 11121722738 for the M20B20, M20B23, M20B25, and M20B27 engines used in a variety of BMW models, including the E12, E21, E28, E30, and E34 3 Series, 5 Series, and 6 Series, among others. Multi-Layer Steel also known as "MLS" head gaskets are preferred as an aftermarket alternative for high-performance BMW engines, including supercharged and turbocharged models, as they offer better performance than factory gaskets.

The M20B20 and M20B23 factory head gasket specifications are 80mm Bore with a thickness of 0.070 inches.

The M20B25 and M20B27 factory head gasket specifications are 84mm Bore with a thickness of 0.070 inches.

MLS Gaskets provide maximum sealing performance for high-output engines, without the need for sealants. These gaskets resist shearing forces and reduce bore distortion with their embossing design.

Comprised of multiple layers of stainless steel, they are durable and corrosion-resistant. Ideal for high-performance engines, MLS head gaskets offer superior sealing and can withstand high levels of heat and pressure.

When choosing an MLS gasket for your BMW, ensure compatibility, thickness, and bore size, and follow installation and torque specifications to avoid engine damage.

MLS head gaskets can NOT be used with motors that have O-rings or receiver grooves around the cylinder bores because they require smooth and flat surfaces to seal.

Cut Ring Head Gasket:

Upgrade your BMW engine's performance with the Athena Cut Ring Head Gasket. This Head Gasket is specifically engineered to replace BMW part #11121722734, 11121722735, 11121722737, and 11121722738 for the M20B20, M20B23, M20B25, and M20B27 engines used in a variety of BMW models, including the E12, E21, E28, E30, and E34 3 Series, 5 Series, and 6 Series, among others. 

Standard OEM & MLS gaskets can only handle a certain amount of cylinder pressures before they start to leak, making the Athena Cut Ring Head Gasket the recommended choice for applications making 16+ psi.

A compression leak passing the head gasket can cause a range of issues, including engine overheating, loss of power, misfires, and in severe cases, catastrophic engine failure.

Athena's gasket is crafted with premium quality reinforced M0115, an asbestos-free material that's original equipment approved and renowned for its superior quality. The AISI 304 stainless steel Cooper Rings bite into the aluminum head, providing maximum sealing capabilities around the cylinder bore and optimizing engine performance, even on engines with nitrous and/or turbo applications that exceed 2 bar boost.

Before installation, it is crucial to have the mating surfaces of the cylinder head and block professionally cleaned and resurfaced to ensure they are completely flat.

Please be aware that the gasket  should have a size that is 0.5mm to 1mm larger than the piston. For example, if the piston measures 84mm, then the gasket should be the next size up, either 84.5mm or 85mm.

Head Gasket Installation Instructions:

1. Make sure that the engine block and cylinder head surfaces are clean, flat, and free from any debris, oil, or coolant.

2. Install the head gasket on the engine block and ensure that it is properly aligned. Avoid twisting or bending the gasket during installation.

3. Place the cylinder head on top of the gasket and install the head bolts or studs in their correct positions.

4. Follow the manufacturer's recommended torque specifications and tighten the bolts or studs in the proper sequence to ensure even clamping force across the gasket.

5. After the initial tightening, re-torque the head bolts or studs after the engine has been started and then allowed to cool to room temperature. This will ensure that the gasket is properly seated and compressed.

6. It is NOT recommended to use any additional sealant on the gasket. Using additional sealant can hinder the performance of the gasket.