Reinforced head gasket Fiat 1.6 Tipo Tempra Uno 159A3 146B7 160A2

The Fiat engines covered

The 1.6 litre petrol engines listed in the table below power the Fiat Tipo, Tempra, Uno, Premio, Elba, Duna, Fiorino, Siena, Punto, Regata and Scudo. Each takes a single cylinder head gasket.

The original gasket of these engines carries part numbers 46414567, 7604404 and 7667675, except on the Scudo's 220A2.000, for which Fiat publishes none. Fiat gives neither the bore, nor the thickness, nor the construction. It is rated for standard combustion pressure; when that rises, the clamping load fades, the head lifts and coolant reaches a cylinder.

Reinforced cylinder head gaskets

Sealing does not rest on the gasket alone: the fasteners that clamp the head to the block play just as big a part. A composite gasket is crushed for good beyond 100 N/mm², whereas the 301 stainless steel of an MLS gasket withstands 517 N/mm² and springs back after every combustion.

This page presents two part numbers from Athena, an Italian maker of competition gaskets, in a single construction: the MLS, a multilayer stainless steel gasket. Both have a bore of 88 mm, with thicknesses of 1.3 and 1.7 mm. As a rule, the gasket bore should exceed the cylinder bore by at least 0.5 mm. Each part number is sold individually: one gasket per engine.

Technical specifications

Gasket volume is the room it leaves above each piston. It adds to the combustion chamber and lowers the compression ratio; compare only gaskets of identical bore, as is the case for both part numbers on this page.

Preparation and fitting

Before fitting, check the flatness of the head and of the block face with a straight edge, then have them resurfaced if needed. Athena supplies this gasket ready to fit: do not coat it with any sealing paste.

Technical guide

The construction offered

Athena MLS A stack of AISI 301 stainless steel sheets, laser cut, stamped and then riveted. Around each cylinder, a sheet folded back on itself, the Gas Stopper, transfers the clamping load onto the combustion chamber, while beads close off the water and oil circuits. The outer sheets receive a two-coat finish: one withstands high temperatures and makes up for small flaws in the block and head, the other, silicone based, stops the gasket from sticking at removal. It is Athena's all-steel solution, from the tuned naturally aspirated engine to moderate forced induction.

Choosing bore and thickness

Gasket bore. The Athena MLS comes in 88 mm for both part numbers, 338251R (1.3 mm) and 338252R (1.7 mm).

Thickness. Fiat gives no thickness figure for the original gasket of these engines. A thicker gasket enlarges the combustion chamber and lowers the compression ratio; a thinner one reduces it and raises the ratio.

Since Fiat does not state the original thickness, read with a dial gauge how far the pistons protrude above the block face, above all if you choose 1.3 mm: that figure sets the clearance left between piston and head.

The brand

Athena S.p.A. is an Italian maker of gaskets and engine parts, with its head office and main plant in Alonte, in the Veneto. The company also has sites in Spain, the United States, Brazil and India. Car makers fit its multilayer gaskets as original equipment, and its whole competition range is designed and produced in Italy.

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 gaskets offered (88 mm) 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: 46414567, 7604404 and 7667675.

Important: the part numbers on this page only apply to the 146B7.011, 146C6.000, 146D6.000, 159A3.000, 159A3.046, 159A3.048, 159B9.000, 160A2.000, 160A2.011, 176A9.000, 220A2.000 and 835C1.000 engines: note your vehicle's 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 does not sag and keeps its shape.

When boost pressure, compression ratio or power goes up, the head gasket becomes the weakest link of the top end. A leak forces a head removal, a job far costlier than the reinforced gasket that would have prevented it.