I have my cylinders off and looking into the intake and exhaust port they look rough and in the intake on the left side there is a little dimple has anybody cleaned up the cylinders port to improve the flow or should I leave them alone , I thought if I sand them down by hand to clean them up it might help a little , any info or pic would help me out if you sand them your self
You do not want to polish the intake port. The intake needs a less than smooth surface to encourage turbulence along the intake tract to help keep the fuel droplets suspended in the air. If the intake surfaces are too smooth you can get fuel drop out and reduce the efficiency of the engine. Big lumps of casting imperfections can be removed and you can also put a knife edge on the leading edge of the centre divider, but do not sand, or polish the surfaces.