moper said

Just my opinion here - I disagree with the choice to not bother addressing the deck issue "because this is just a torque engine". There are two things that need to be "right" in my mind: crank centerline, and deck height. The factory machining sucked. All of it. so if technology exists to correct the result of the scuking, then I'm all for using it. The end goal is higher performance than a factory engine. Whether performance be horsepower, torque, emissions, economy, or a combination of some or all. So with that in mind - The crank centerline (or main bearing bore centerline) is one two bores that modern machining equipment uses to index itself. Every engine I do gets the mains honed and the decks square decked. Because everything is related to those being a given spec. "Zero deocking" is BS in terms of a description because it can be any height that leaves the piston flush with the deck surface. It's a minor misuse of a word but you can have a small block deck "zero decked" and that deck hieght could be 9.590, 9.600, 9.550 all depending on the accuracy of the main bearing bores, the crank, rods, and pistons used. Decking is the action of milling the gasket surfaces of the block. Depending on the block, the machinist, and the milling equipment used this could be a good or bad thing as there is no reference to setting a deck hieght or correcting any relationship of the deck to anything else. Square decking is machining the head gasket sirfaces in order to make them parallel with the crank centerline, perpendicular to the bores, and set at a known height. Because the deck surface placement and accuracy affects individual cylinder compression ratios (static and dynamic), gasket sealing, valvetrain stability, and individual pushrod lengths it IS that important to get as perfect as possible.

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