Has anyone ported and polish? Is there any gains? and does anyone have any pics of them doing it?

 

if your thinking of this your better off having someone do it that has a flow bench etc. You can do more damage than good if you don't have the proper tools.

 

Agreed... Changing port shapes can change the way the air flows... Even though your thinking your doing good you could be doing harm... If anything i would only "gasket match" the ports.... This SWEET diesel builders guide shows pics of how BAD the Duramax is gasket matched stock. Not sure about Cummins. If i pull my manifold off for any reasone id just do a gasket match.

 

lots of gains in port and polishing, and gasket matching,
if you do it yourself just make sure all the ports are semetrical and are the same size when your done, you can use one of those berret things when your done to measure them in cc's