You can clean up any imperfections, I have found better flow going wider than taller on the neon heads. The only exception was the SOHC head (Not the Magnum) That little buggar needed all the help it could get, but even then, I ended up going alot wider than I did taller. The magnum just has a better designed port. You want to make sure you cleaned up the exhaust bowl area good too. They too seem to have the nasty ridge around that needs to be tapered down.