My 500 B motor (400 block) uses a 4.15 crank and 6.76 (440 length) rods with chrysler big ends, for a rod stroke ratio of 1.63. the oil ring is in the pin boss, and I have issues with piston slap. If you use a chevy rod length and big end you may not need to clearance anything. I was stubborn, and wanted chrysler spec rods. .