I'll probably buy one of those expensive eyeball swivel vents for the back seat of my -8, but all I wanted for the front was a simple on-off vent valve up under the panel. A Van's eyeball vent is too leaky, as is a DL-019 valve from Aviacomp; I didn't want any winter drafts. So where to get an inexpensive precision vent valve?
A quick trip to a friend's auto repair shop netted a 50mm throttle body from the junk pile. A few passes through the bandsaw and a few minutes on the lathe pared it down to just the basic throat and butterfly. Add a bracket, a handle, a bit of nylon for a friction lock, and maybe a dot of epoxy to plug any air bleed holes.
Endless variations on the theme are possible.
A quick trip to a friend's auto repair shop netted a 50mm throttle body from the junk pile. A few passes through the bandsaw and a few minutes on the lathe pared it down to just the basic throat and butterfly. Add a bracket, a handle, a bit of nylon for a friction lock, and maybe a dot of epoxy to plug any air bleed holes.
Endless variations on the theme are possible.
