You guys must have the charm, I tried to attach a pdf yesterday and was told "nyet".
The only thing that those graphs show is that there was a change in power with an apparent change in AFR. Apparent because there was also a change in timing, although based on the limited info available, its probably real. The spark plugs will confirm or disprove that. Expand the scale, but it looks like a large jump in AFR. In any event, the timing and fueling go hand in hand, so yes the timing curve could have, and probably did, change the Hp.
I was going to write that the only way to compare /device, no device/ would be ABBA test with the same fueling and timing (and if relevant, carb spacing & plenum volume)
However, then I read that the recent test was done in 2nd gear and the previous test was done in 3rd gear. That changed load, lets the engine spin up faster, and I wouldn't trust the AFR interpretation either, although it shouldn't have been effected - I've seen it happen.
As far as the temperature and humidity go, that can be mostly addressed using a corrected Hp calculation. However it is important to be sure the Dynojet software has not be changed, and that the fuel is the same. Fuel differences can be partly addressed by using lamda instead of AFR, but there still may be Hp differences. Best off using something consistant.
With all that, then the device can be compared to determine if it is really the cause of the change. A MAP (or vac gage) would help understand what is going on. To recap: Get the timing, load and AFR the same. Same carb, spacing and plenum volume. Then the comparison will be mostyly what is wanted: whether the device changes the vacuum, the atomization or distribution in a way that makes a difference to power.
