Here is my reply from SC , could well be right !
Ok, if you look at column D, this is the air flow, there is no air flow until nearly 4,000rpm when it starts to rise, which also follows with Column F with the ignition advance, it shouldn't be getting near to 20 degrees advance until much further up the rev range, even then it would be in the mid teens. Then when you look at Column E, you see why, it isn't on full throttle until 3880rpm.
As such it look like you have a problem with your throttle.