1. The problem statement, all variables and given/known data How many revolutions does a driving shaft of an eight cylinder four stroke engine perform until every cylinder has ignited once ? 2. Relevant equations 4 - 8 - 6 - 2 3. The attempt at a solution Moreover, I would like to have information and understand the logical solution of the question. Can anyone explain me as detailly as he/she can ? Thanks in advance!