Reinforced cylinder head gasket Honda Accord Torneo 2.0 F20B

The Honda engines covered

The 2.0-litre Honda F20B petrol engine is fitted to the Accord (VI and VII) and Torneo models detailed below.

Honda publishes neither the part number of this engine's original gasket, nor its bore, nor its thickness, nor its construction. That gasket matches standard combustion pressure: when it rises, clamping eases off, the cylinder head lifts and coolant passes into a cylinder.

Reinforced cylinder head gaskets

The head gasket does not seal alone: the fasteners that clamp the head to the block contribute just as much. Above 100 N/mm², a composite gasket settles with no recovery; the 301 stainless steel of MLS gaskets holds up to 517 N/mm², 5 times more, and springs back with every combustion.

This page presents the part numbers of Cometic, an American maker of competition gaskets, in one construction only: the multi-layer steel MLS. All the gaskets have an 86 mm bore and thicknesses from 0.69 to 3.56 mm, enough to adjust the compression ratio without touching the pistons or the cylinder head. As a rule, the gasket bore chosen is at least 0.5 mm larger than the actual cylinder bore. Each part number is sold individually, one gasket per engine.

Technical specifications

The gasket volume is the void it leaves above each cylinder. Added to the combustion chamber, it lowers the compression ratio, the more so as it grows. Compare these values only between gaskets of the same bore.

Preparation and fitting

Before assembly, check with a straight edge that the head and block faces are flat, and have them resurfaced if needed. Add no sealing paste: Cometic gaskets are supplied already coated.

Technical guide

The construction offered

MLS Cometic Stainless steel layers, stamped and then riveted together. The outer layers show active beads around each cylinder and each fluid passage. A moderate tightening torque is enough to seal and the bore barely distorts. This all-round solution suits anything from the prepared naturally aspirated engine to moderate boost.

Choosing bore and thickness

Gasket bore. The Cometic MLS is offered in 86 mm (C4634), in that bore alone.

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

Before choosing a thickness below the original, measure with a dial gauge how far the pistons protrude above the block face: it shows the clearance left between piston and head.

The brand

Founded in 1989 in Concord, Ohio, Cometic Gasket, Inc. designs gaskets and sealing solutions for engines. It made its name with the made-to-measure gasket, cut to the bore and thickness requested. All of its production stays in the United States, using American 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 original gasket, a value Honda does not give 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: part number not published by the manufacturer.

Important: the part numbers on this page match the Honda F20B engine: check your vehicle's engine code before ordering.

Why switch to a reinforced gasket?

When the original gasket is no longer enough, the reinforced gasket takes over: under higher combustion pressure it keeps its shape and does not crush.

Turbo, supercharger or a raised compression ratio: loads on the cylinder head increase and the gasket becomes the most stressed part of the top end. A reinforced gasket prevents the leak, and the head removal that follows.