sentences:  A typical firing order of L-R-L-L-R-L-R-R (or R-L-R-R-L-R-L-L) results in uneven intake and exhaust pulse spacing for each bank.When separate exhaust systems are used for each bank of cylinders, this uneven pulsing results in the rumbling sound that is typically associated with V8 engines.However, racing engines seek to avoid these uneven exhaust pressure pulses, in order to maximise the power output.