Ok, I am about a 7th through this thread, but have read all of those 135 pages so far. I will be picking up a drum on Tuesday night, so now it is time to gather the rest of the parts. As I live in the Netherlands, we have our fair share of cold and wet weather. With slightly more of our share of rain. ;) That means that I want to be careful to use intakes and exhausts that do not allow water in, as I want to be able to 'set and forget' instead of continually looking outside to see whether there are any drops of rain. So, I already found a 2.4" stainless exhaust which essentially is a large 90 degree bend. I guess that would work.
For the intake I would like to use a single intake. Just to cut costs and add simplicity. Rummaging around in the garage I found a Bosch butterfly valve off a car. It is a NOS part that I got off the shelf of a dealership that went bust. I haven't got a clue what car it is from, but it has a very nice 1.5" intake and a good venturi effect being over 2" first, then going to 1.5" where it passes through the valve. I am thinking of creating a mechanism to adjust the opening of the valve with a gas cable. But, would the intake and exhaust sizes work in your opinion?