An ADI Crankshaft Designed for High Performance in TVR's Tuscan Speed Six Sports Car

The TVR Tuscan Speed Six, (produced by TVR Engineering in Blackpool, England) is a high performance automobile, by any measure. This low volume sports car weighs 1,100 kg (2,420 lbs) and is powered by a 4-litre in-line six-cylinder engine that develops over 350 bhp and 310 ft-lb of torque. TVR Engineering selected an Austempered Ductile Iron (ADI) crankshaft for its combination of low cost, low weight and high torsional strength. Not since Ford dabbled with ADI in its race cars in the 1980's has a manufacturer chosen ADI for its crankshafts. Although virtually all the major automotive producers and the Motor Industries Research Association (MIRA) have investigated ADI for use in crankshafts, this is the only known production application of ADI crankshafts in automobiles.

ADI presents a useful set of properties for the design engineer. With ever increasing specific power requirements for new engine designs, new material/process combinations for engine components are being explored. This paper will discuss the properties of ADI, the reason for its selection for this crankshaft, and its suitability for this application.