advice on bore and pistons?

[saridout]

You can't possibly pre-determine or even see minute scoring.

good point. i guess i'll get everything else pulled off of it and just take it over to the shop. at least now i have an idea now of what i'll need, i.e. oversize pistons instead of standard. thanks!

[Phred]

64imperial,

You're close, but not quite correct. After 30+ years in the race engine, machine shop business, I can tell you the prefered sequence of events that lead up to a block being overbored. Preferably, a block will be brought in for work with the main caps torqued on. It's really up to the machinist to advise the owner what steps he should take. Most shops will first clean the block, then do a dial bore check to determin the worst spot in the worst cyl. The machinist will then know which oversize to buy. He will also have options or preferences of which pistons to buy. After the pistons are in his hands, he will do the work, once. Machinists don't generally like to start a job, set it aside, then pick it up and finish it later. That is not an efficient way to do business, and will be more labor intensive. Most replacement type pistons will also come with rings, and pin. He will will need to know what type of rings are supplied to be able to hone the cylinders with the proper grit stones. While your at it, you will probably need to have the old pistons pressed off, and the new ones installed. When its all done, have them final clean the block and reinstall the oil galley plugs. When you get it back, it should be ready for assembly.

Phred