should head gasket be slightly bigger than the bore size

ie 88mm bore/pistons and rings

88.5 mm head gasket

If your buying cometic gaskets mate, it's thickness they are ordered in.

Headgaskets are slightly bigger than the bore size.

Generally you would go with 1.2mm cometics, if that's what your using and yep would be fine with 88mm pistons. This size piston would require a slight rebore though, whereas the 87.5mm ones would require just a deglaze-hone the bores (slightly cheaper and the extra 0.5mm of piston will gain you nowt)

hth

smithy

If your buying cometic gaskets mate, it's thickness they are ordered in.

Headgaskets are slightly bigger than the bore size.

Generally you would go with 1.2mm cometics, if that's what your using and yep would be fine with 88mm pistons. This size piston would require a slight rebore though, whereas the 87.5mm ones would require just a deglaze-hone the bores (slightly cheaper and the extra 0.5mm of piston will gain you nowt)

hth

smithy

 

cheers paul

been advised to get bored to 88mm slightly damaged blockl, and a few damaged pistons

Oopps! in that case yep wap the 88's in and if fitting cometic it will be spot on for you, just order the 1.2mm set.

cheers

smithy

dont know what you mean by 1.2 mm

 

ive ordered 88m

0.51"thickness as they put it at z1 motorsport

 

ive also just had an e-mail from them stating that they use 1m bigger gasket to piston

 

so 88mm piston/bore would use 89mm gasket ?

Aye the US use thousand's of an inch, mm is soooo much easier , lol just checked their site and the 0.51" relates to 1.2mm

But yes your right, sorry getting confused they do a cometic now 1mm over bore size, never used to years ago when i first started selling :D

smithy

Aye the US use thousand's of an inch, mm is soooo much easier , lol just checked their site and the 0.51" relates to 1.2mm

But yes your right, sorry getting confused they do a cometic now 1mm over bore size, never used to years ago when i first started selling :D

smithy

 

right

so what do you think i should do

 

as i have already ordered an 88mm gasket

should i get it bored to 88mm, or should i just have it honed to 87.5, which would leave me with 0.5mm bigger gasket ?