I might be retarded buuuuut...

[A-98]

the inlet is totally where the red part it, you can see by the orientation of the place where the diafragm(or do QEVs use light weight pistons?) would go, pluss the pilot is aalways opposite the outlet, so the hose barb is the outlet

[noname]

OK, everybody, we're not getting in a huge b!tch fight over this.
imforcedtodothis, make your chamber and screw it into the red part. Make sure you have a pilot valve in the QEV. Pressurize it. If it holds pressure, you know you have it right, if it doesn't, I'll slap myself for being stupid.

[Killjoy]

If your wrong we'll want to see a video of you slapping yourself, but your probably not and i would bet money that the part with the red is the inlet.

[imforcedtodothis]

my bad i miss read what stuff wrote...that seems kinda weird that the part with the hose barb is the inlet.

well, i looked in the holes and it looks similar to a barrel sealing piston valve... so now the barbed part is looking like the outlet.

[noname]

Hah!
I don't have to slap myself!
You couldn't get video footage even if you wanted too, I can't figure out how to take videos with my brothers new camera.

[imforcedtodothis]

OK, everybody, we're not getting in a huge b!tch fight over this.
imforcedtodothis, make your chamber and screw it into the red part. Make sure you have a pilot valve in the QEV. Pressurize it. If it holds pressure, you know you have it right, if it doesn't, I'll slap myself for being stupid.

well, slap yourself now. i only get one chance at this, it has to jb welded into there, it has no threads. if worst comes to worst i can geta custom part to fit in there (my uncle owns a machine shop haah).

[noname]

Glue it in there with some silicone sealant. It'll only hold about 40 psi, but it will be leak free and you can test if it's the right side before epoxying the chamber in.
Why didn't you get a threaded QEV?

[imforcedtodothis]

the QEV's on ebay always have the wrong information so you just have to deal with it. its not that big of a problem but its would be nice to have it threaded. how much would a 1" tap cost, do ya think?

[noname]

A 1/4" tap is over $7 at my local Ace hardware, a 1" is over $20. Just screw a 1" steel nipple into it to cut threads.

[Insomniac]

Well I think the inlet is the red plug, and the outlet is the barb. You can see where the gas is ment to flow in the second pic, and seeing as its basically a diaphram valve you can see how the diaphram sits and how it seals onto the tube that has the hose barb.