Hey guys... I've been lurking here for a long time but I rarely post. I'm working on my first Sch-10 stainless manifold and have a couple of quick questions about finishing my T4 divided collector.

1. Should I weld the inside first, or the outside first? Both 2 into 1 splayed collector sections are already tacked inside and out. The first time I tried this, I welded the outside first and the inside seam split apart, making it impossible to weld up nicely on the inside. So I'm assuming I should just weld the inside first, right?

2. Do you guys bevel the edges of the splayed pipe in the same manner as a butt weld on pipe? I'm assuming since it's going to be welded inside & out, that this is not necessary to achieve good penetration.

3. Should I completely weld both 2 into 1 splayed sections of my T4 collector and then cut the bottom flat and insert into a press to make the oval (to match my flange)? Right now the two pipes merge into a 360* circle. I'm assuming here that it would be best to fully weld, then cut, then press form the end into an oval shape... then weld to the turbo flange.

Any advice would be appreciated.