The air door on a TQ is the venturi for the secondaries. It has everything to do with mixture control.
Good luck finding secondary jets for a TQ.
Once opened nothing, might give a little ‘choking’ action in the millisecond before fully opened. I’d look to see if the jets might be clogged a little.
the larger the opening the less the pressure differential is on the secondary fuel tube. the harder the draw the more fluid vol. you get.
