What size guru fan do I need for a UDS that has a 3 ft piece of pipe coming up with the ball valve on top? It recommends a pit viper 10 but that is for UDS without the extra pipe. Should I get the pit viper 25 or will the 10 push enough air down the pipe? Here's a link to a picture of drum and to the pipe I am referring to.
http://www.smokingmeatforums.com/t/98999/1st-build-done
http://www.smokingmeatforums.com/t/98999/1st-build-done