I just put my 1.6L SM on the dyno for a test/tune and wanted to share the results with everyone. I have a Sunbelt engine with roughly 30hrs on it. Compression is 204, 204, 203, 204, and leakdown was slightly less than 1% on all cylinders. Basline going into the tuning session was 12deg spark advance, stock (unopened) AFM, used iridium NGK plugs (normal heat range), pump gas 93 octane, Mobil1 10W30 High Mileage formula + 1qt. Mobil1 V-twin. I also just installed a 5X AFPR. The intake is home made, but looks very similar to the SPX straight intake.
I have to say, the biggest take away is how minor the changes to power and torque are when tuning. You need to be very consistent when making the runs. One of my goals was to see if the unopened AFM school of thought is better than the tuned AFM school of thought.
All numbers in the graphs are uncorrected. The day started around 65deg and ended at 69deg. The SAE correction factor stayed stable at 0.95, and the STD correction factor stayed stable at 0.98 (humidity went down as the temp. came up). I'll let you do the conversions if you want.
First thing I looked at was fuel pressure. The graph below shows three fuel pressures, each run is a 1.0psi adjustment in pressure.