The SD-455 was one of only a few regular-production Pontiac engines to receive heat-treated, forged-steel connecting rods. Designed by Pontiac engineers and produced for Pontiac by Continental Motors, the SD rods have the same overall dimensions as the standard cast-iron rods used in all other production engines. As a direct replacement for stock cast rods, once word was out, many racers were ordering these rods over the parts counter for their own applications. Orders flooded the parts departments, leading to...