From what I've seen at the track and read in Corky Bells book, it's pretty hard to muck up the hot side as long as it stays sealed and doesn't melt. I wouldn't lose any sleep over the set-up you have there. What material are you using? "Looks" a lot like the 304 s.s. I used. Slow to weld, but has held up well.
I ended up using just plain steel, with a few pieces of stainless mixed in (some pieces I just couldn't find in non-stainless) I used my MIG to weld it together, and I have never welded stainless before, so I decided to go with plain steel. I wouldn't mind having it ceramic coated, but I am going to just paint it with some VHT Flameproof and then wrap with some lava wrap.
