The small brass tube in the intake chamber.
Do I need to clean it out if it is blocked?

http://i22.photobucket.com/albums/b341/yellowLT1/CIMG0320.jpg

Thanks

I do not know for sure exactly what the tubes do, but I would run something through them if clogged.

I never paid them much attention but I did blow through each one with my air compressor. None were clogged in mine. Your head looks cleaner than mine was. I could actually knock carbon chunks off.

It jets air in at an angle, introducing swirl into the incoming charge. For high performance headwork they're usually removed. Probably not a big difference either way, but the factory usually doesn't go to that much trouble unless there's some benefit.