Engine Machining

I have a green 454 block that I want to stroke into a 496. Normally, I would take it to a NAPA shop but this time I took the block to a Performance machine shop. They are telling me that they can't bore it unless I have the whole rotating assembly because the pistons may not each match to the 4.310 bore. I have always thought that any size difference in pistons would be minimal and this is why you size and gap rings. Should I wait to get the rotating assembly or call the BS flag and have them torque plate hone each bore to 4.310?  

What do you mean by performance machine shop? Is build performance engines the only thing they do?  

Yea, They do racing engines and balance/blueprinting  

I'd listen to them personally. They are trying to their job and they know what they are doing. It will cost but you'll have one helluva motor.  

just because a piston is .030 over doesn't mean that the bore will actually be .030 as well

the different materials used for pistons require a different spacing between the piston and the bore...which means that yes, they do need the pistons to finalize the bore diameter

and the rest of the rotating assembly for mock-up to ensure that there is no clearance issues between the rod ends and the pan rails, pistons and the crank counter-weights, crank counter-weights/rod ends and the bottom of the cylinder bores  

Give them what they ask for. To do a quality job its all needed.  

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Horsepower sells Engines and torque wins races.

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Horsepower sells Engines and torque wins races.

i used keith black .030 pistons for my 400sbc, machine shop told me the same thing... good thing i listened to them becuase when i got home and started file fitting my rings, all the bores were off slightly  

Theres a slight difference in piston size and thats why each cylinder has a piston fitted for it. Just make sure the machineshop has marked each piston for the cylinder it was honed for.