Hey guys. The current head on my van has a valve seat that drops every once in a while, so I am preparing to put a new head on. I have a spare swirl turbo head that is a non-oem unit with the non-magnetic exhaust valves. In photo one there is a casting error in the bowl. It doesn't touch the fire ring area, what do you guys think? Anything this may cause? Second photo is where i smoothed out the flaw. Third photo is me taking a shot at mildly de-shrouding the valves with a carbide bur (It's mild as I don't want to reduce the compression much). I made some sheet metal pieces that covered the valves and also used a scribe to be sure the deshrouding is all the same distance outwards. I still need to smooth it out with sanding rolls. Feel free to tell me if I did anything wrong. I will do the same to the other 3 chambers, and then turn my attention to the runners. For that I will take the valves/ seals out.