Question is answered: 273 Engine Block Decking

most blocks are not square....but I would not just cut it .015 on deck...I would want the block squared.

Usually you are shooting for a zero deck on your piston deck clearance whereas went the piston is at TDC is it even with the deck of the block....In doing that you need to add 1/2 the stroke of the crank..plus the length of the connecting rod and plus the Compression height of the piston....this number is given to the machine shop and that what the deck is cut too...the blocks are uneven left and right and front to back....what is you want is it squared.

With a LA block you are usually shooting for a 9.599 deck height...but you can have him square the deck but only take a minimal amount off.

you might want to ask what kind of machinery he uses to square the deck...