Influence of Crankshaft Material and Design on the NVH Characteristics of a Modern, Aluminum Block, V-6 Engine

The NVH characteristics of a modern, aluminum block, V-6 engine were shown to be nearly equivalent when a cast ductile iron crankshaft with multi-mode damper was substituted for the production, forged steel crankshaft with conventional, single torsional mode damper. This result contradicts the traditional thinking that suggests forged steel crankshafts produce better NVH characteristics than ductile iron crankshafts. Also, a lightweight, cast ductile iron crankshaft with multi-mode damper showed only slightly inferior NVH characteristics than the production, forged steel crankshaft with single torsional mode damper. The substitution of cast ductile iron for forged steel can also result in significant cost and weight savings.