air-box pressure

[M4 Ed]

I have a v-twin drag bike with side scoops and an air box for my 4 throttle bodies. Because of problems with air pressure variations in the air box caused by the draw of the alternating 80 ci cylinders we have not used a map sensor to read and adjust for the building box pressure as the bike accelerates to 173mph. Instead we add 2% fuel in 3rd, 4% in 4th and 6% in 5th.
I recently tried activating the map sensor and removing the gear comp.
Even as it rises with MPH, the pressure in the box is also constantly fluctuating a total of 14kpa. This I believe is created by the cylinder draw and possibly some vibration.
My problem is that in I2-standard I can only display actual and effective pulse width and they are constantly in sync with effective be lower by .5ms whether the map sensor is on or not. (by on I mean that in fuel/map comp 100kpa=0, 110=10, 90=-10 and sensor setup is 105)
My question is why don’t I see the ms adjustments that should be being applied to the injectors.
Thanks Ed

[RossB]

Fuel Effictive Pulse Width is the base fuel time with trims and compensations already added. On an M4 it is not possible to log the trims seperately. Fuel Actual Pulse width is Fuel Effective Pulse width with the Injector Dead Time Comp added, as this is normally fairly constant (unless the battery voltage changes) the two channels will have a fairly constant offset from each other. Fuel Effective Pulse Width represents the ammount of time the injector is actually open.

The fluctuations you are describing could be caused by a number of things. What type and make of MAP sensor are you using? How is it mounted? Do you have an air filter in your air box?