Fuel tank venting opinions

[ULTM8Z]

I run a Tanks EFI fuel tank on my 1971 Camaro.

The only issue I found with the supplied check valve from Tanks is that fuel vapor can leak out of it when the car is off. The garage ends up smelling like raw fuel.

I run an EFI system based on GM TPI electronics and run the factory 1990 Camaro solenoid operated charcoal canister. Wanting to use that, I retrofitted a 1990 Camaro venting system. So I wanted to retain the factory style vent system.

For the fresh air intake, I run the factory "mushroom" valve that mounts near the rear axle on most third gen Camaros. This hooked up to one of the vent ports on the Tanks unit.

For the vacuum line, in order to avoid sucking fuel into the canister, I drilled and tapped a 1/8 NPT into the filler neck as close to the gas cap as possible. I then installed a 90° hose barb and ran the vapor line from there into the factory '71 steel vent line that runs to the front of the car and ultimately terminates at the canister.

Been running this set up since Jan 2015 and works perfectly.

[WSSix]

Thanks for the replies everyone.

Ultimate, I don't have any of the purge or vent lines connected on my canister. I just have the vent line terminating into it. See anything wrong with that other than not being optimal?

Thanks

[ULTM8Z]

In principle, all the tank needs is a vacuum source to suck fuel vapors out and a fresh air source that can supply air at least at the same rate as the vacuum source purges the tank. Also, the vacuum line set up in such a way as to disallow liquid fuel from being sucked in (which, by experience, my setup seems to achieve).

In which case, on the tank itself you only really need one line in and one line out (which is what I have).

I'm not familiar with all the hook ups on a 96 formula canister, but I can't imagine it's too much different than my '90 TPI unit.

My canister has only two hose connections:

1.) Main vent line to the tank

2.) Constant vacuum source. The vacuum line actually hooks up to the electronic solenoid mounted on top of the canister. The ECM controls the solenoid open/close as to when to start/stop purging the tank.

[Che70velle]

Trey, I contacted Tanks upon receiving mine, and asked this same question. The vent that they send will only allow venting inwardly, which is fine since the tank needs this as the pump is pumping outwardly. I was concerned that perhaps I needed a vented gas cap, and the tech told me absolutely not.
There is no way that the supplied vent they send can allow fumes to enter the garage. It's a one way vent, and works well on mine, with no fumes in the shop at all. Make sure you mount it higher than the tank, and your golden.

[WSSix]

Thanks Scott and Ultimate. I need to look at my canister again. I believe I have three line connections.

[ULTM8Z]

I must have gotten a defective check valve or something... when I put my nose to it I could literally smell the fuel vapors coming out of it.

Any rate, check valve or no, I still prefer the factory set up.

[dhanks]

I use II Much Fabrication vents and they work well.