Thread: Chevy 283 holes in pistons

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Here's a good stout hypereutectic piston. Note that the compression height is 1.805" This is the type of tall CR piston you will want to use. It will allow you to get to a 0.035" to 0.045" squish (zero deck) without taking too much meat off the block decks.
KB Pistons for Automotive Applications

I was just writing this for a member on another forum, but it will suit you as well......

First thing you will want to do is determine the stack you will use. On a 283 Chevy, the stack of parts used is the sum of the connecting rod length (5.703"), the radius of the crank stroke (1.500") and the piston compression height (measured from the centerline of the wrist pin to the crown of the piston. This measurement for a 283 is normally 1.800", but there are "rebuilder special" pistons that have a shorter piston compression height. They are made shorter so that if the machine shop decks the block, say 0.020" (twenty thousandths) to freshen the surface, then you can buy pistons with a 0.020" shorter compression height (1.780") and maintain the same piston deck height. Best advice is to purchase 1.800" (or taller by a few thousandths) pistons. Choose a piston crown configuration that will work with the cylinder head combustion chamber volume to produce a static compression ratio that will work with pump gas without detonation. Current thinking puts this at 9.5:1 max using iron heads and 10.5:1 max using aluminum heads.

Take the block to the machine shop and have the technician check the main bearing bore for being round and parallel. If the holes are out of round or do not line up, have the block align-honed or align-bored to correct the main bearing bore. This is the cornerstone of the motor. If the mains are not machined to factory specs, then everything else will be skewed in the motor.

Next, knowing the stack of parts you will be running, have the shop to index the block off the main saddle and cut the block decks to zero piston deck height. For instance, if your stack measures 9.008", (1.805", 5.703" and 1.500"), then cut the block decks to 9.008" block deck height from the main bearing centerline. Most small block Chevy blocks will be in the 9.025" block deck height range from the factory. What we're doing is setting the block up square so that we will have the proper squish using a 0.039"/0.040"/0.041" head gasket thickness. We're also squaring the block so that the heads will sit squarely and properly on the decks......so that the intake manifold will sit squarely and properly on the heads and will seal up each and every port so that you don't have any vacuum leaks or any cylinders pulling oily vapors through the bottom of a port that is not sealed up because the heads are askew on the block.

Resist the urge to use anything in the oiling system other than stock-type parts. If you want to use a larger capacity pan, fine, just match the oil pump pickup to the pan, leaving about 3/8" clearance between the pickup and the bottom of the pan.