Head Gasket Bore 77mm, Bore 76.5, Is This Ok?

[R33GTS25]

Hi,

Not an RB motor but, what is the "general rule" about clearance between the bore size of the gasket and the actual bore size of the engine?

Is 0.5 mm clearance enough?

Thanks.

[GTRsean]

. Should be sweet. In general head gaskets are a little bigger than the bore, eg: 86.5mm bore, you would use an 87mm gasket.

[R33GTS25]

. Should be sweet. In general head gaskets are a little bigger than the bore, eg: 86.5mm bore, you would use an 87mm gasket.

Yeah, knew they were a little bigger but how much bigger was my drama.

Ive also been told you can have them exactly the same size as the bore as long as the piston doesnt hit the gasket it should be fine.

Thanks.