Most piston /ring kits come in .010" , .020",.030",.040" oversize
most engine re-conditioners use cnc borers set to an over size and bore to that
after honing to get the correct cross hatch pattern in the bore , that is it
the ring gap is what is important and it should be around .003" per ever 1" of bore
so for a 3" bore the gap should be around .010"
experience has proved that if the cylinder is bored to say .020" oversize then when the gap for .020" oversize rings is checked ,it generally comes in around .015 and even as large as .020"
max specs for ring gaps is .025" which is for a worn cylinder
just honing a bore is a waste of effort as bores wear in a taper ( larger at the top than the bottom and this taper increases the wear of the new rings and can lead to broken rings
the ridge at the top of the bore has to be removed to allow the piston to come out easily and to prevent piston failure when the new rings are fitted
have a talk with engine reconditioning shops and then make an informed decision
remember that if the cylinder can be separated from the crankcase , you can buy standard or oversize piston/ring/cylinder sets as assemblies so there is no need to bore out or hone.
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