The piston position at BDC reveals two things. First, that the long connecting rods are needed to prevent piston-skirt-to-crank-counterweight contact with the long stroke. Second, that the tall deck height of the block is required to accept the combination of stroke and rod length. This combo would stick out the top of a stock Chevy block by about 516 inch. Dougan's measured the overall length of a stock Chevy cylinder as 5.750 inches at a 9.025-inch deck height; the Dart cylinders are longer at 5.8925 at a 9.325 deck height.