Use a table ban saw to hack off the 340 piston crown .

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Keith Black Pistons KB243-030 Fits SB Chrysler 340 Flat Top 6cc Bore 4.070

Fits SB Chrysler 340, Bore 4.070, Stroke 3.310, Rod Length 6.123, Flat Top 6cc, 2 Valve Relief, Compression Height 1.840, Set of 8 Pistons

The deck height of all small blocks are the same. 9.60 inches

Deck Height and Compression Distance Data