I've mounted a Mustang-style fuel tank in the trunk of my '41 Buick (and yes, I'm fully welding in a firewall between the trunk and the cabin). I know these are popular tanks in customs...what are you guys using for a vented filler neck? I can make something that will work if I need, but if there's a short, off-the-shelf steel neck with a vent line that's available that would be even cooler. The ones I've found so far are too long, too rubber, or too tacky looking. This is basically the same set-up @DirtyNapkin did in his '40 Buick, but there's no photos of the filler neck on his build thread and I texted him about it but he's blowing me off because he's a famous custom builder now and doesn't have time for us little guys Any input's appreciated...thanks. Curt
Just use what ever filler neck you can get, stick a hose barb in the side of it and run a piece of fuel line out of the trunk. Do not use a vented cap. Just for information only, NHRA does not require a fully welded firewall unless you are running fuel cell and battery both in the trunk. I think that a fully welded firewall is a good idea, just general info and nothing else.
My boat takes a fuel tan vent like this one. Takes a 5/8 hose that might be a pain in the trunk but a guy could stick the vent in a discrete spot as long as it vented outside the car.
My tank is not vented plus I wanted a rollover valve in place. So I welded a bung in the filler neck to screw the valve into and use a non vented cap.
That's what I was looking for. What is that short filler neck that you used? Did you just drill and tap the fitting into the stub that's on the tank?
This isn't my set up but I think you could probably use a cut down 50s F-100 truck neck or similar. I usually pick up filler necks at swap meets if they are cheap enough. I recently bought a 54 Pontiac filler neck and a 67 Mustang but I believe both have a curve on them so they aren't straight like an F-1 is.
The Jalopy Journal
