i have several intakes. i have one hole almost directly below the heating element, about 1.5" in diameter, and another intake on the side that is also about 1.5" in diameter. The one directly below the heating element is always open, and i have yet to open the other intake. i've never tried to plug the bottom hole, and am not sure if it would change things much. all i know for sure is that it works extremely well when smoking jerky!
my main problem that i have found overall is the temperatures that i am able to reach using my 1500W smoker element i got off cabelas. I am only able to get up to about 275 in the winter (30-40*), and it takes me over 3 hours to get there. I've been slowly looking to upgrade to a larger element, but want to stay away from the 220v elements that i see are popular. i've even thought about purchasing another 1500W element and stacking it on top of the original one, but am not sure if that would get me higher temperatures, or if it would just increase the rate that the temperatures increase..... any advice on this would be greatly appreciated!
Happy Smoking!