Does the AFM angle/orientation matter

[Sagaris]

I am wondering if anyone with a custom air intake setup has had to change the orientation of the AFM and if there were any adverse effects from doing so. I understand how the AFM works and that gravity might help or resist movement of the flap inside the AFM depending on how it is mounted. I do not have a wideband O2 yet and will not be able to see any impacts on fuel mixture.

I understand that I sound like a total dork asking a question pertaining to an air intake setup but I am curious to see whether anyone has had any issues or knows if AFM mounting position is much of a factor at all.

[NigelStu]

I use the AFM angle and clock-spring tension as AFR tuning devices on my SpecMiata.

Got the position/spring close on the track with an Innovate wideband.
Final tuning was done on a dyno with a sniffer up the tail-pipe.


One thing to note, its not just gravity and airflow that plays with the door. Longitudinal and lateral accel will move it too. The AFR numbers can look funny on the track if you're recording the data...

[Knockenwelle]

I'm using an M30 AFM with a big K+N cone and heat shield, and I had to flip it sideways to fit. I have noticed that gravity seems to make about 1-2 clicks of difference in what the car wants.