Got truck running after some new stuff and didn't pay any attention to the new boost elbow set screw. Got done bleeding out lines and let her idle a few minutes looking for leaks. Ran down the street and back up then shut her down for the night. Checking for any more leaks this morning I noticed the allen set screw is MIA. What size is it and how do you keep it from backing out? This one was not much more than finger tight to start with. I didn't want to Loctite it until I got it dialed in. Any help appreciated.

 

7.0? mm X 1.0? thread seems to fit. Can anybody confirm this? Temp bolt in with a jam nut for now. Loctite blue when I get another allen set screw.

 

Looks like the actual thread size is 6.0mm X 1.0mm pitch on this one. The replacement screw is still very loose in the threads so now I wonder if it is not some offsize SAE thread that I don't have an example of laying around. I tried every SAE of that size in my collection and always got tight about 2 threads in so I reckon it is metric since 6mm threads in completely, just looser than I expected.

Now to properly tune the beasty

 

Just disconnect and plug the hose to the waste gate actuator all together, then you won't need the elbow.

 

if you can't find the right size at Ace Hardware, then drill and tap it with the next size up and then you know you will have the right fit.

 

Mine turned out to be a 6MM X 1.0MM pitch screw.

And the reason I didn't just plug it is that I am running a stock HX35 and don't want to have to worry about overboost and running off the top of the turbo's operating map. Trying to keep it at about 30 psi max. With a stock air box and a ProGuard I am probably already choking it some.