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Reduced price! Reinforced cylinder head gasket Nissan FJ20E FJ20ET 2.0L View larger

Reinforced cylinder head gasket Nissan FJ20E FJ20ET 2.0L

New product

Reinforced Cometic head gasket in multilayer MLS for the Nissan 2.0-litre 16-valve engine.

  • Engine: FJ20E FJ20ET
  • Bores: 90 and 91 mm
  • Thicknesses: 0.69 to 3.56 mm

More details

127,79 € tax incl.

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170,39 € tax incl.

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  • The Nissan engines covered

    The 2.0-litre 16-valve Nissan FJ20E petrol engine is fitted to the Silvia S12 in the version detailed below; the Cometic part numbers on this page are announced by the maker for the FJ20E and FJ20ET.

    Nissan publishes neither the part number of the original gasket of these engines, nor its bore, nor its thickness, nor its construction. That gasket is built for standard pressure: when pressure rises, the clamping load relaxes, the head lifts off the block and coolant escapes into a cylinder.

    Reinforced cylinder head gaskets

    The head gasket does not seal on its own: the fasteners that press the head onto the block count as much as it does. Above 100 N/mm², a composite gasket settles for good; the 301 stainless steel of MLS gaskets withstands up to 517 N/mm², 5 times more, and recovers its shape at every combustion.

    This page gathers the part numbers of Cometic, an American maker of competition gaskets, under a single construction: MLS, a multi-layer steel design. The gaskets exist in 90 mm and 91 mm bores, and in 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

    Gasket boreThicknessGasket volumeGasket type
    OEM not specified
    BrandPart number
    90 mm0.69 mm4.39MLSCometicC4326-027
    90 mm0.76 mm4.83MLSCometicC4326-030
    90 mm0.91 mm5.79MLSCometicC4326-036
    90 mm1.02 mm6.49MLSCometicC4326-040
    90 mm1.14 mm7.25MLSCometicC4326-045
    90 mm1.30 mm8.27MLSCometicC4326-051
    90 mm1.42 mm9.03MLSCometicC4326-056
    90 mm1.52 mm9.67MLSCometicC4326-060
    90 mm1.68 mm10.69MLSCometicC4326-066
    90 mm1.78 mm11.32MLSCometicC4326-070
    90 mm1.91 mm12.15MLSCometicC4326-075
    90 mm2.03 mm12.91MLSCometicC4326-080
    90 mm2.13 mm13.55MLSCometicC4326-084
    90 mm2.18 mm13.87MLSCometicC4326-086
    90 mm2.34 mm14.89MLSCometicC4326-092
    90 mm2.49 mm15.84MLSCometicC4326-098
    90 mm3.05 mm19.40MLSCometicC4326-120
    90 mm3.56 mm22.65MLSCometicC4326-140
    91 mm0.69 mm4.49MLSCometicC4327-027
    91 mm0.76 mm4.94MLSCometicC4327-030
    91 mm0.91 mm5.92MLSCometicC4327-036
    91 mm1.02 mm6.63MLSCometicC4327-040
    91 mm1.14 mm7.41MLSCometicC4327-045
    91 mm1.30 mm8.46MLSCometicC4327-051
    91 mm1.42 mm9.24MLSCometicC4327-056
    91 mm1.52 mm9.89MLSCometicC4327-060
    91 mm1.68 mm10.93MLSCometicC4327-066
    91 mm1.78 mm11.58MLSCometicC4327-070
    91 mm1.91 mm12.42MLSCometicC4327-075
    91 mm2.03 mm13.20MLSCometicC4327-080
    91 mm2.13 mm13.85MLSCometicC4327-084
    91 mm2.18 mm14.18MLSCometicC4327-086
    91 mm2.34 mm15.22MLSCometicC4327-092
    91 mm2.49 mm16.19MLSCometicC4327-098
    91 mm3.05 mm19.84MLSCometicC4327-120
    91 mm3.56 mm23.15MLSCometicC4327-140

    The gasket volume is the empty space it leaves above each cylinder. It is added to the combustion chamber and reduces the compression ratio, the more so as it is large. Compare these values only between gaskets of the same bore.

    Preparation and fitting

    FastenersEnginesTightening torque
    Original cylinder head boltsFJ20E, FJ20ETnot published by the manufacturer

    Before fitting, check with a straight edge that the head and block faces are flat, and have any that need it resurfaced. Apply no gasket sealant: Cometic gaskets come already coated.

    Technical guide

    The construction offered

    Cometic MLS cylinder head gasketMLS Cometic
    Stainless steel layers, stamped and joined by rivets. The outer layers carry active beads around each cylinder and each fluid passage. Moderate tightening is enough to seal and the bore distorts very little. This versatile construction ranges from the prepared naturally aspirated engine to moderate boost.

    Choosing bore and thickness

    Gasket bore. Cometic MLS comes in 90 mm (C4326) and in 91 mm (C4327).

    Thickness. Nissan discloses no thickness for the original gasket of this engine. A thicker gasket enlarges the combustion chamber and lowers the compression ratio; a thinner one reduces it and raises the ratio.

    Your goalThickness to choose
    Keep the original compression ratioOriginal thickness unknown: measure the removed gasket and keep the nearest value offered
    Skimmed cylinder head, make up the lost heightThe offered value closest to the figure measured on the removed gasket, plus the thickness taken off when resurfacing
    Forced induction build, lower the ratioA thickness above the one measured on the removed gasket
    Naturally aspirated build, raise the ratioA thickness below that of the removed gasket, down to 0.69 mm, the lowest of the range

    If you choose a thickness lower than the original, first measure with a dial gauge how far the pistons protrude above the block face: this figure gives the clearance that remains between piston and head.

    The brand

    CometicFounded in 1989 in Concord, Ohio, Cometic Gasket, Inc. is an American company that designs gaskets and sealing solutions for engines. It became known for the made-to-measure gasket, cut to the bore and thickness required. All its manufacturing stays in the United States, using American materials.

    Advantages over the original gasket

    CriterionOriginal gasket: part number not publishedReinforced gaskets
    ConstructionConstruction not stated by the manufacturerMulti-layer stainless steel (MLS)
    Gasket borenot published90 and 91 mm
    Thicknesses availablethickness not published by the manufacturer0.69 to 3.56 mm, 18 values
    Compression ratio adjustmentNoneThrough the thickness chosen
    Resistance to overpressureLimited to standard outputDesigned for forced induction

    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, which Nissan does not disclose 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

    BrandModelEngine codePowerYears
    NissanSILVIA (S12) 2.0 GPFJ20E146 hp1984-1988

    OEM part number: part number not published by the manufacturer.

    Important: the part numbers on this page match the Nissan FJ20E and FJ20ET engines: read the engine code of your vehicle, then check the bore, before you order.

    Why switch to a reinforced gasket?

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

    As soon as a turbo, a supercharger or a higher compression ratio comes into play, the head takes more load and the gasket becomes the most exposed part of the top end. A reinforced gasket stops gas or coolant leaks, and the head removal that would follow.