'.1. An SI engine operating at 1200 RPM has a 10.2-cmbore with the spark plug offset by 6 mm from center. The spark plug is fired at 20° bTDC. It takes 6.5° of engine rotation for combustion to develop and get into flame propagation mode, where the average flame speed is 15.8 mIsec. '-2. Calculate: (a) Time of one combustion process (i.e., time for flame front to reach the furthest cylinder wall). [see] (b) Crank angle position at the end of combustion. It is desired that flame termination be at the same crank angle position when the speed of the engine in Problem 7-1 is increased to 2000 RPM. In this range, flame develop- ment takes the same amount of real time and flame speed is related to engine speed as VI ex 0.92 N. Calculate: (a) Flame speed at 2000 RPM. [m/sec] (b) Crank angle position when the spark plug should be fired. (c) Crank angle position when flame propagation starts.