Couple things about your dyno run. Have them zoom in before they print the graph, so you get higher resolution. Also, don't use "shootout" mode, rather match the acceleration on the dyno to what you see on the street in the same gear. Placement of the temp sensor makes the numbers with this dyno vary greatly. I can almost guarantee they have their "x" number too high as well based on your mods/power numbers/maf readings.
Hi, we had a group discount, was cheap, I went for it
You can you guess the power output based on MAF readings alone?