Any ideas where this hose goes please

[threedogs]

In the process of getting some fittings together to increase the size of the pipe on my ZD30
from OE to 3". from the airbox to the turbo,there is one hose that goes back to the air box,
but does any one know where the push on after market fitting goes to,
is it a balance tube ??
The picture is of an aftermarket set up

[mudski]

John the oem pipe has two hoses going to it. One is from the catch can, the other is to the air resonator box. That setup on the picture you have I reckon that small hose goes to the needle valve. As they are not using the resonator box anymore for the needle valve vacuum bleed supply, they have simply gpne straight to the air intake for vacuum bleed.

[threedogs]

Thanks Mark, looks like I wont need it, which is good
Might have a go at making a stainless lid with a 3" outlet

[mudski]

Where is your needle valve picking up the vacuum bleed now?

[threedogs]

teed off on the vac pump side of dawes

[threedogs]

Do you or Mullet-hunter still have the OE maf housing ??

[mudski]

teed off on the vac pump side of dawes

What about the other side of the needle valve?