If those are your min/max volts from you datalogs than that is good, I was just looking for spikes there. Are you running 8v regulated power to the crank sensor as suggested in my writeup? Does the crank ground go to the Megasquirt? Is the signal wire shielded? If all is true, then have you noticed my comment about soldering in those extra capacitors to greatly stiffen up the overly sensitive MS1 processor maybe the MS2 needs the same capacitors.