Machining a block, how it´s going???

Hi Guys,

got some confusion around me, hope some of you expirienced Guys can help me out. I want a machine shop to bore and hone my block, called the guy today and he said it´s necessary to have the pistons at the same time. I said the bore is bad, don´t know wich size it must have to be clean, i think it´s more than .030 over(can i know it before?). He insists getting the pistons before. I planned to order the pistons if i know which size the finished bore is. who´s right?

Ok, i understand that the correct piston to wall clearance can only be measured if you have the piston you want to run in this engine, but i don´t know if he´s honest to me and just want to sell his stuff.

how do the machine shops in U.S. do this work? do they finish a bore with the biggest size needed to clean up the walls (and small as possible) or do they take a specific piston and machine the bore according to the piston?

thanks in advance

Greets Michael