I actually get what Nissan says it is 14,4 kilometres and I've been at 15,2 and 14,2 and no speedometer tolerance, actual miles, want to know more, PM me can show you proper spark just compare, for vacuum it is not so hard just get some fitting replacement rubber hose and do not check for worn, just replace if never done before. For timing, you will need to put ecu in timing mode so just don't touch idle screw and mechanical ignition advance yet or you will mix up ecu and it will run weirdo