You would not believe how hard it is to get Y Pipes etc. The only ones I found were the same size through out the whole Y. I would need to build my own to do that. The 3" to 4" 90* reducing bend will take care of the whole thing and it will be nice and clean too..
There is a big thought process that goes on with a build like this, you change one thing and it affects the next. You are forced to think 2 or three steps ahead which is a BRAIN STRETCHER at least for me anyway!:dontknow:
