built this last week, feel free to critique. I know the design is a lil funny but I the customer wanted to keep A/C and Power steering, Also I had to leave room for the 3 inch downpipe.

 

Good job, i know how hard it can be to build a tubular manifold while keeping both ac and power steering in a miata. The inside of the collector doesn't look pretty, but anybody in the know understands that it is perfect for the application. Welded on the inside and blended, not something you see everyday

 

looks good, i know those miata's are kinda tricky tomake everything line up, with the damn water hose where it is.

also i woud just say nxt time throw on ali more of a bevel on the pipes so you can get a flat bead that is still filled in penty. also it will help you keep the bead more uniformaround the pipe.

 

thanks alot guys! I will try all of the advice given. I'm always trying to learn and get better. and yes the water line is a major PITA

 

I like it.

Question about the welding. Looks like you're hitting about an inch at a time before a re-position. How long do you wait on a tube before getting it hot again, or do you just bang it around the tube until it's done?

 

I honestly just reposition it and keep welding, Im sure thats probably not the right way to do it but if the metal is ridiculously hot then I set it to the side and start on another piece.

 

the only thing id be concerned with is how much grinding youve done on the inside of the collector. how do you know when you have ground it too thin? it looks like you are using a carbide bit. why not just weld the seems together? it would still be smooth and you wouldnt have to worry about cracking because the metal was too thin.

 

after I was done welding the inside seams I just ground everything smooth. The only parts that I really applied pressure to were the welds themselves. I did large beads on purpose so I would have extra material to knife edge. The rest of the piped I just scuffed up with the carbide bit.

 

the porting or smoothing that he did is perfectly acceptable and desireable. After looking at the welds one more time I can see some contamination. I would either start and stop more often or purchase a larger cup with a gas lens. again good work!

 

looks good