Ok thanks I'm gonna continue working on them. How much is too much gritty? Because with the 240 grit it still leaves sanding lines. Is 240 the final drum you use??
Seeing sanding marks if fine. Feeling them all "gritty" is what I get rid of. Just feel the factory casting, and see how rough that is in the intake port. Don't go for the glass look and feel. I think I use 120 grit.