yes, that's the first ever turbo manifold I made, and it uses a 15deg merge collector cut with a makita cutoff saw
Took ages to clean the edges up with a file so the aligned perfectly, if you cut it with a bandsaw it's a lot cleaner, I have quite a few photo's of jigs you can make to cut perfect 4 runner collectors everytime.
I can't get my camera to take a good enough photo showing the metal point in the middle where they meet, but I didn't have to weld down in there or do any grinding to get the nice point.
If making collectors is too hard for you, you can also buy them from many places online like BMCrace, burns stainless, etc etc. either plain or pre-welded.
Here's some photo's from the construction of that manifold showing the points that join up in the center of the collector, it's not welded from the inside, I dont have a lava nozzel. I used a gas-lens to weld down between the runners into the middle of the collector, the gas lens allows you to get enough stick-out to get right down in the middle. I'm only a novice welder but I think this one turned out ok, there was decent penetration in the welds
DIY collector with a chop saw guide is here:
I'll post some pics of bandsaw collector jigs if anyone wants them. I'm getting a bandsaw soon so making things like collectors will be much easier.
