screamer is basic 180 pulses, big bang i think is like 180 but fired like a set of twins or one twin two singles and the last is set like a v8 crank 90 lobs but only four pots but you need to think of power duration how much of a stroke is under power so from TDC to BDC how many degs is power ? this is how v engines gain , more degs under power per rotation .