Help with 440 Block Machining Questions

[john108]

 Help with 440 Block Machining Questions (Casting Date 11/30/76).
I have concerns on how a machinist will/should machine the block.
The goal is to achieve tight quench.
Recommendations have been made to mock-up the assembly before a final deck machining.
I would expect that after initial inspection of the block, the stroker kit can be purchased.
I have been told at machine shops that after line-bore, they have to machine the deck square because they use the deck as a datum to machine the piston bores. 
This procedure would require machining the deck twice, because the bore is too small initially to do a mock-up first.
The standard deck height is 10.720 and tight quench (with a kit similar to 440source 505 cu-in) deck height would be 10.705.
That only leaves .015 to square it up and then achieve tight quench.  Not much material assuming that the stock blocks are nominal and it is machined twice.
IS mock-up necessary??  The machinist suggested that the assembly parts are usually very accurate and they would machine the block based on adding up the detail dimensions based on specs.
What should I insist on?
Stroke          4.250   
Stroke/2                       2.125
Rod Length (special)       7.100
Piston CD (special)       1.480
Sum                       10.705
       
Stock Block Approx.   10.720   

[firefighter3931]

John, most if not all of the stroker kits are configured to allow for some wiggle room. This means that the pistons will end up being slightly below deck to allow for squaring up the deck surface and achieving a true zero deck. I would definately have the machinist mock up the rotating assembly and measure afterwards....that way you are 100% sure of what you got. 

My old 446 using a 68 block needed some decking ; the right and left banks were different and the front and back of the block was also off a bunch ; .005 front to back on the driver side bank    Gotta luv "factory" machining 


Ron