Composite head gaskets are thicker than standard tin gaskets and will therefore lower the engine's compression ratio. Ideal for correcting compression ratio when heads/ block faces have been skimmed. (Not applicable 1995 on).
Approximate gasket thicknesses are as follows:
Standard (tin) gaskets 0.5mm
Composite gaskets 1.2mm
Typical effect on compression ratio:
Standard (tin) gaskets 3cc
Composite gaskets 10cc