Calculate the mean piston speed, bmep, and specific power of the spark-ignition engines in Figs. 1-4, 1-9, and 1-12 at their maximum rated power. Calculate the mean piston speed, bmep, and specific power of the diesel engines in Figs. 1-20, 1-21, 1-22, 1-23, and 1-24 at their maximum rated power. Briefly explain any significant differences a.direct injection four stroke cycle six cylinders turbocharged commins diesel engine.displaced volume10 litres, bore 125mm,sroke 136mm, compression ratio 16.3, maximum power 168 KW to 246 KW at rated speed of 2100 rpm.