Reinforced head gasket Volkswagen Audi 1.4 TSI TFSI EA111

The Volkswagen and Audi engines covered

The 1.4 litre petrol engines with sixteen valves and four cylinders in line, listed in the compatibility table below, are fitted to the Volkswagen Golf V, Golf VI, Golf Plus, Jetta III and IV, Passat B6 and B7, CC, Scirocco III, Eos, Tiguan, Touran and Beetle, as well as the Audi A1 and A3. Each takes a single cylinder head gasket.

Four original part numbers are recorded: 03C 103 383 AM, 03C 103 383 R, 03C 103 383 AE and 03C 103 383 AH. The manufacturer publishes neither their bore, nor their thickness, nor their construction. Sized for standard combustion pressure, these gaskets give way when it climbs: the clamping load eases, the head moves away from the block and coolant reaches a cylinder.

Reinforced cylinder head gaskets

Sealing does not rest on the gasket alone: it also depends on the fasteners that press the head onto the block. A composite gasket crushes for good beyond 100 N/mm² of stress, whereas the 301 stainless steel of MLS and MLX gaskets withstands 517 N/mm², 5 times more, and springs back with every combustion.

This page brings together three part numbers from two competition makers: two Cometic (United States) MLX gaskets, with a 77 mm bore and thicknesses of 0.81 and 1.02 mm, and one Athena (Italy) MLS gasket, with a 77.8 mm bore and a thickness of 1.0 mm. The engine takes a single gasket: pick one part number, according to the bore and thickness you want.

Technical specifications

Gasket volume is the free room it leaves above each piston. It adds to the combustion chamber and lowers the compression ratio; compare only gaskets of equal bore, since the Cometic and the Athena on this page differ on that point.

Preparation and fitting

Before fitting, lay a straight edge across the head and the block to check their flatness, then have them resurfaced if needed. Cometic and Athena supply their gaskets already coated: add no sealing paste.

Technical guide

The two constructions offered

Athena MLS Athena MLS A stack of two to five AISI 301 stainless steel sheets, laser cut, stamped and then riveted. A folded sheet surrounds each cylinder and forms a Gas Stopper, which passes the clamping load towards the combustion chamber, while beads isolate the water and oil circuits. The outer faces are coated: one layer withstands heat and fills small flaws in the block and head, a silicone layer keeps the gasket from sticking when removed. It is Athena's all-steel solution, from the prepared naturally aspirated engine to moderate boost.

Cometic MLX A stack of stamped, riveted stainless steel sheets, with a folded centre sheet that forms a stopper around each combustion chamber, and a high-temperature coating. The clamping pressure concentrates around the cylinder without distorting the bore. It is the sturdiest all-steel construction in the range, to be chosen for hard boost.

Choosing bore and thickness

Gasket bore. The Cometic MLX is offered in 77 mm (C4980-032 and C4980-040) and the Athena MLS in 77.8 mm (338433R).

Thickness. The manufacturer gives no thickness for the original gaskets. A thicker gasket enlarges the combustion chamber and lowers the compression ratio; a thinner one reduces it and raises the ratio.

With the original thickness left unstated, use a dial gauge to measure how far the pistons stand proud of the block's gasket face, especially if you aim for 0.81 mm: it sets the clearance left between piston and head.

The two brands

	Athena S.p.A. is an Italian maker of gaskets and engine parts. Its head office and main factory are in Alonte, in the Veneto; the group also runs sites in Spain, the United States, Brazil and India. Its multi-layer gaskets are fitted by car makers as original equipment, and its whole competition range is designed and built in Italy.
	Founded in 1989 in Concord, Ohio, Cometic Gasket, Inc. is an American maker of engine gaskets and sealing parts. Its speciality is the made-to-measure gasket, cut to the bore and thickness requested and produced entirely in the United States from local raw materials.

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 the gasket offered (77 mm for Cometic, 77.8 mm for Athena) 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: 03C 103 383 AM, 03C 103 383 R, 03C 103 383 AE and 03C 103 383 AH.

Important: the part numbers on this page only suit the engines in the compatibility table: note your vehicle's engine code before ordering.

Why switch to a reinforced gasket?

When the original gasket is running out of steam, the reinforced gasket takes over: under greater combustion pressure it does not flatten and keeps its shape.

Add a turbo, a supercharger or a higher compression ratio to this four-cylinder and the head gasket becomes the first weak point of the top end. A reinforced gasket rules out the leak, and the head removal that follows, far dearer than the part.