#1 I have a different approach altogether for inlet air t5hat is much easier and less expensive to construct. It also allows for much more air when you want to go high temp (like for grilling pizza).
#2 The goesinto should equal the goesoutof
#4 you can get by with a more gentle burn-in. No need for creating a big spectacle.
I got a photo album here:
I can also email you a guided PowerPOint presentation if you PM me your emaill address.