Quote:
Originally Posted by GRX
Ahhh ... engine blueprinting. Seems to me such variances can be attributed to quality control at the factory. It would be nice if a machinist calibrated the equipment for each individual block. But that would be too time consuming & expensive when doing large production numbers. This is why no one single number can be tied down since no two are exactly alike.
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Dittos. There is NO "norm". Since every block/crankshaft/piston/connection rod has variances in the casting/forging/machining processes, there isn't one set amount of material to remove. I have two '72 400 blocks under my workbench. One has a block height of 10.240 inches (std height). The other is 10.245 inches. BOTH are virgin block. Likewise, I've seen pistons with .002-.005 variance in compression heights in the same set; connection rods with .003-.005 variance in rod c-to-c length in the same set. Let's not get started on crankshafts. I've seen them as much as .020 out of stroke from the factory. To realistically zero deck a block, you first have to measure all the components and establish what the zero deck height should be. Then, machine the block accordingly.