400 port and polish ?

I doubt you will lose any performance. The blending and grinding away of casting flash and "flow trips" will improve performance. It looks like there was some reshaping done as well to control intake charge velocity. What "rough" does, and rough is a relative term, is keep the boundry layer flow turbulent, which helps keep the fuel atomized. If you are concerned about it, take the head to a good machine shop and have them glass bead the intake port. You'll be "In like Flynn" and it won't cost you much. (Be sure they mask off the seats, guides, etc first!)

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