Hello. I drive a 1992 na. For the first time I should mention, during the head seal change the cylinder head was 2/10 mm planed. In addition, I set the zzp to 14° v.ot. Below it did not pull soo well and from 6,500 rpm ging the needle no longer so fast, so became a bit sluggish. Consumption was 8.2 l with super. 50/50 sporty and sprite saving. I have today put super Plus and you can say what you want it to go off now!!! He had not knocked because of the hö He always had a jerk at low revolutions at full load, which I push on the old spark plugs. (Come on again). I will calculate the consumption with super plus at the next time. Do you have any experience with it? Maybe someone who has changed the zzp and or compaction himself. Do you think the consumption could be less? Something? So with MIR with my engine settings it definitely brings real performance and not just imaginary, e r is better at all speeds both below and above. Achja . End silencer is self-made with less congestion pressure. Short secondary question: if I have a roll and a consumer in idle mode as well as e.g. the ventilation it jerks. Without a consumer it runs round. What can that be? Evtl sharp camshafts from the previous owner??? Thank you very much for your answer!!!