Reinforced cylinder head gasket Volkswagen Golf 3 Vento Passat Corrado Sharan Transporter T4 2.8 AAA AMY ABV AES

The Volkswagen engines covered

The petrol engines on this page, of 2.8 and 2.9 litres capacity, carry the codes AAA, AMY, ABV and AES. They power the Volkswagen Golf III, Vento, Passat B3 and B4, Corrado, Sharan, Transporter T4 and California T4 in the table, from 1991 to 2000. With a single cylinder head, the gasket is sold individually: one is needed per engine.

The original gasket carries part number 021 103 383 L. The manufacturer publishes neither its bore, nor its thickness, nor its construction. It is sized for standard combustion pressure: when that rises, the clamping load drops, the head lifts and coolant reaches a cylinder.

Reinforced cylinder head gaskets

The bolts that clamp the head to the block provide half of the sealing by themselves: the gasket cannot manage alone. A composite gasket is crushed for good from 100 N/mm², whereas the 301 stainless steel of the MLS gasket takes 517 N/mm², five times more, and recovers its shape at every combustion. This also concerns the Volkswagen engines on this page.

This page brings together the part numbers of the racing manufacturer Athena, in multilayer MLS construction. Gasket bores run from 82.5 to 84.1 mm, in two thicknesses, 0.65 and 1.65 mm.

Technical specifications

Gasket volume is the space the gasket leaves free above each cylinder. That space adds to the combustion chamber and lowers the compression ratio; here, both the bore and the thickness change from one part number to the next, and the volume changes with them.

Preparation and fitting

Before fitting the gasket, check the flatness of the cylinder head and block with a straight edge, and have them resurfaced if needed. The Athena gasket is supplied coated: do not apply any sealing paste. It applies to each of the three part numbers offered here.

Technical guide

The construction offered

Athena MLS A pile of two to five AISI 301 stainless steel sheets, laser cut, pressed and then riveted. A folded sheet, the Gas Stopper, surrounds each cylinder and directs the clamping load toward the combustion chamber; beads separate the water and oil circuits. The outer faces receive two coatings: the first resists heat and makes up for small flaws in the block and head, the second, in silicone, prevents the gasket from sticking at removal. It is Athena's all-steel answer, from the prepared naturally aspirated engine to moderate boost. On this page, these are part numbers 338314R, in 82.5 mm, 338320R, in 84.1 mm, and 338321R, in 83 mm.

Choosing bore and thickness

Gasket bore. The Athena MLS comes in 82.5 mm (338314R) and 84.1 mm (338320R), both 0.65 mm thick, and in 83 mm (338321R), 1.65 mm thick.

Thickness. The manufacturer publishes no thickness for the original gasket of these Volkswagen engines. A thicker gasket enlarges the combustion chamber and lowers the compression ratio; a thinner one reduces it and raises the ratio.

Since the original thickness is not published, measure with a dial gauge how far the pistons stand above the block deck: the figure shows the clearance left between piston and head with the 0.65 and 1.65 mm thicknesses.

The brand

Athena S.p.A. designs and manufactures gaskets and sealing parts for engines. Based in Alonte, in the Veneto, with other sites in Spain, the United States, Brazil and India, the brand also supplies some car makers as original equipment. Its competition range is born entirely in Italy, from design to production. Part numbers 338314R, 338320R and 338321R are the ones on this page.

Advantages over the original gasket

When a reinforced gasket becomes necessary

• Adding forced induction, or raising boost on an already turbocharged engine
• Cylinder rebored beyond what the bore of original gasket 021 103 383 L, which Volkswagen does not publish covers
• Looking for a compression ratio different from standard, higher or lower
• Engine that has already lost its gasket, or is consuming coolant
• Competition use, where the gasket goes through repeated temperature rises

Vehicle compatibility

OEM part number: 021 103 383 L.

Important: the gaskets on this page are listed for the Volkswagen models in the table, from 1991 to 2000. For any other vehicle, note the engine code before ordering.

Why switch to a reinforced gasket?

When the original gasket reaches its limits, the reinforced gasket takes over: under higher combustion pressure it keeps its thickness and shape instead of being crushed. The Volkswagen AAA, AMY, ABV and AES engines get three part numbers here.

Fitting a turbo or supercharger, or raising the compression ratio: as soon as power climbs, the head gasket is the first link in the top end to give way. A reinforced gasket prevents the leak and the cylinder head removal that follows, far costlier than the gasket. This holds for the Volkswagen models in the table as for any hard-driven engine.