Reinforced head gasket BMW M50B25 M52B25 M52B28

We offer you here several reinforced head gaskets for M50B25 engines with and without VANOS, and for M52B25 / M52B28 single and double VANOS, from the ATHENA and COMETIC brands, whose technical characteristics you will find below.

Below (click on the image) you will find the head studs / bolts for the BMW M50B25 engine:

Technical characteristics of the original gasket

• Engine bore: 84mm
• Thickness: 1.75mm

Technical characteristics

• Engine bore: up to 84.5 or 85.5 or 86 or 87mm
• Thickness(es) of your choice: 1.60 or 2.00mm
• Gasket type: O-Ring
• References: 330012R, 330144R, 330013R, 330011R, 330014R

Designed and manufactured in Italy, the Athena reinforced head gaskets are available in two forms:

• MLS: these gaskets are made up of several sheets of stainless steel, superposed and riveted together. The stainless steel sheets are laser cut for increased precision and receive an elastomer-based surface treatment (NBR or FKM). To achieve optimal sealing, the contours of the cylinders and the water and oil passages are stamped / embossed. For the most extreme applications, reinforcement at cylinder level is added.
• O-Ring: these gaskets consist of a steel sheet covered with asbestos-free aramid fibre and an AISI 304 stainless steel ring (at cylinder level). A bead of silicone applied to critical points (water and oil passages) ensures maximum sealing of the head gasket. This gasket type is mandatory for heavily boosted engines.

Technical characteristics

• Engine bore: up to 85mm
• Gasket type: MLS or MLX
• Number of layers: 3, then 5 for gaskets from 1.42mm thickness
• Thickness(es) of your choice: 0.69, 0.76, 0.91, 1.02, 1.14, 1.30, 1.42, 1.52, 1.68, 1.70, 1.78, 1.91, 2.03, 2.13, 2.18, 2.34, 2.49, 3.05, 3.56mm
• References: C4328, C4328-027, C4328-030, C4328-036, C4328-040, C4328-045, C4328-051, C4328-056, C4328-060, C4328-066, C4328-070, C4328-075, C4328-080, C4328-084, C4328-086, C4328-092, C4328-098, C4328-120, C4328-140, C14010, C14010-067

Founded by Bob Gorman in 1989, the Cometic brand is recognised worldwide as a leader in the design and manufacture of reinforced head gaskets. These, like all of the brand's products, are made in the United States. Cometic reinforced head gaskets are made up of several stamped stainless steel sheets held together by rivets. There are three types of Cometic head gaskets:

MLS: equivalent to the Athena MLS gaskets, these multi-layer gaskets (between 3 and 5 stainless steel sheets depending on gasket thickness) feature embossing around the cylinders and fluid passages.

• MLX: this gasket has an identical base to the MLS gasket but adds reinforcement (folded sheet) at cylinder level and a special high temperature coating.

• HP: this is an MLX gasket with an additional layer added, the purpose of which is to reinforce the sealing of the cylinders (see below)