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The forged RPM crank is part two of Toki's plan to make power with a 396. This is a 4.250-inch-stroke crank, making it about as big as you can go in a production big-block. Toki's argument is that the long stroke helps the engine breathe better in spite of the undesirable cylinder heads. During the intake phase, having a longer stroke allows the intake charge to build more velocity in the runners. The pistons' longer dwell time at bottom dead center allows the intake charge to maintain that velocity of airflow into the cylinders even as the pistons start to travel back up the cylinders for the compression phase. In short, the long-stroke crank allows for better cylinder filling through these cylinder heads than a stock stroke crank. Yes, it physically moves more air, but the key is how it causes the air to move.