Keep whatever pipes you had the motor ported for. I dynod my Hjr dune ported cyls I had with t5s and then Cpis. There was hardly a noticeable difference.
What is the compression at? what bore are the cyls on? stock cyl? just 1 new clutch spring? is it 1 or 2 carbs? you put jetted carb. what kind of head and what size domes?