So I put my FD up on jeckstands to make a new exhaust and recirc the WG dump, and found what appears to be hardware missing from my wastegate. I can't tell what brand it is, and I don't know what is missing (at least some cap screws, maybe also a spring? Or a stud and a couple of lucknuts?).

Here is the WG (the dump tube had another 3" on it, I had just cut it to put a nice mandrel bent piece of 2" on it to join back into my DP):



Notice the two threaded holes?

 

I think I have looked at 1000 pics of wastegates. I can't find who made this one : (

 

Center is usually some kind of adjustment. Very similar to my wastegate(hks). I have a bolt in the center and the outer one is a vacuum port

 

Yeah I am sure one is a vacuum for the diaphram and the other is the spring preload... But if I knew the brand I could call them and ask for a parts list so I don't have to guess on the hardware.

EDIT: I am also thinking this one should have the boost controller input to the diaphram only, since there seems to be only one port on it. I know some get both manifold/controller.

 

Looks like a CX racing wastegate or some offbrand, 50mm maybe?

The center threaded area for preload adjustment is probably M6x1.0, though on a lot of the chinese wastegates they dont put a plate above the spring to give the bolt something to push down on. You could take it apart and inspect, if it's lacking the plate a properly sized freeze plug will work.

The other threaded bit is for using an electric boost controller with a 3-way valve. It should be 1/8 NPT