Im in the process of finishing up my Motion and I have a set of 575 Sci going in....Now the question is the actual thru hull pipes that bolt onto the stock header...I would like to go with a 5 or 51/2 inch out the back....can it be done and what are the pros and cons...

Thanks

My CMI's are 5" tails (on Big E tops) that go right through the transom. CMI provided stainless rings and rubber gaskets for in the engine bay and outside on the transom, for the pipes to fit through and seal. I also covered the bare wood with a resin so water couldn't penetrate.
Tails are "dry" and water dumps at the end of the pipe.
DAVE