I recently bought a project car of a some ancient build of a Turbo miata with the goal of modernizing it and restoring it to modern specs. I've gotten to working on the intake and the turbo and I am absolutely confused of why this is built this way?
From the pictures that should be posted along with this, there seems to be a line that goes from the Turbos outlet and then splits off into a T connector with one going to the Tial Wastegate, and the other going to a... Husky valve that goes no where?
There is also an electronic valve that just goes no where and nothing goes to it... it's just hanging out there? (Link of the valve: https://www.clippard.com/part/EVO-3-12-H)

Does anyone have some ancient wisdom of why this was put together this way? When I look up the regulator, I see posts of people saying its a "great/beautiful home depot boost control", but then why is it hooked up this way with it leading to nothing? I am about to replace the whole line with a new line that simply goes straight from the outlet to the wastegate, or maybe buy a boost control, but I'm a strong believer in that if someone did something, they did it for a reason. Was this some hack method to keep the engine from blowing up or something? My guess is that it was some crude boost manual boost control and the original builder was not only cheap on his parts but also cheap on his health so he had an aneurysm half-way through the build. Any more reasonable ideas definitely welcome.


Here is the EV just hanging out....

The T connection junction? The smaller line is from the turbo outlet and the bigger lines go to the Husky Valve and the Wastegate

The Husky valve

The whole Frankenstein line, it was put together this way with the line sticking way out to be accessed near the intake

 

Looks like a ghetto-*** way to control boost. Bleeding off wastegate pressure to atmo? I'd ditch that in favor of a proper MBC, or EBC through your ECU if you are modernizing.

 

Possibly plumbing from a water or nitrous injection?

 

Turn one way to increase boost. Other way to default wastegate pressure.

 

From your post, it sounds like the previous builder was trying to implement a boost control system but ended up with a somewhat haphazard setup.

 

I've never seen a Husky valve used that way to control boost, but that's the idea there. The electronic valve was likely used in place of the manual valve first, but either failed or didn't every work correctly, so they went with an unusual mechanical way to raise boost pressure above the wastegate pressure.

I would remove it and run wastegate pressure first.

 

Seems like a DIY boost control setup to me. Venting to atmo seems odd, but it would cause the wastegate to see less pressure. Certainly not the way I think would be recommended, but it seems like it would work OK.