I've been porting my P.I. heads on the exhaust side and in the chamber for sometime now to where it looks good (hopefully flows well). I've been using a dremel tool with barrell rollers with rough, mild, and fine and does a good job. I haven't touched the intake ports at all. i cant get all the way down to the bottom but i've been told to leave them alittle rough to still keep some turbolence. what do you guys suggest? go down as far as i can and work up?