look inside my exhaust elbows.....

this saturday I got to works on the elbow..remove the hose to clean, to then sandblast them.
I took some pictures of this carbon build up in the inside walls.. they were almost 1/2" blocking part of the exhaust..



and this is how they look after blasting them


you can see the surface is still rough though..smoothening it would improve flow?

I also cleaned the accumulated gums rust in the water passages..

will plaint them next..