Hi,
Please, could you share your thoughts regarding clunk type setup for aerobatic or 3D plane?
While braking in gas engines on stand I noticed that clunk with filter on it is still providing fuel w/o air bubbles untill the last drop of the fuel in the tank while over 90% of the filter is exposed to the air.
I am wondering why air is not coming through exposed to the air part of the filter ???
Any guess or ideas?

So far I have been using regular clunk and forced to land with 50% fuel in the tank as I see that engine starts coughing after ~ 10-15 min in the flight.
I guess clunk starts picking up air in half empty tank.
What if I will use clunk with filter?
I hope occasional exposure to the air in half empty tank with new clunk may give me bubble free fuel flow.
Then I can reduce tank size and use saved weight for more aggressive 3D ..
Please, share your thoughts on this topic.
Thank you,
AK.