Head Gasket Sizes

[cactu5]

Hi guys,

I'm in the process of rebuilding my rb26, it is getting bored out 20 thou to 86.5mm. I'm buying a metal head gasket at the moment and I have noticed that Cometech only make an 86mm and an 87mm head gasket.

My question is how important is it to get an 86.5mm metal head gasket? What will happen if I don't?

One person I spoke to said that I should just get an 87mm gasket, and that would be fine.

[humz]

yes thats correct, 87mm will be fine im using the same one on standard pistons

[cactu5]

Thanks mate, that's good to know.

[Duncan]

now thats what we thought too....so why are there 86 and 87mm head gaskets if it doesn't matter? or maybe .5mm is ok but 1mm is too much