opinions on vapor recovery system please

[69hugger]

I am doing a bunch of upgrades & freshening this winter on my Camaro, and have now been able to fully see the plumbing of the evaporative system that was installed, I think by DSE when they installed the F.A.S.T. fuel injection system 4-5 years ago. (I bought the car last year), and am hoping some of those up on these things can help me figure out what to do with it.

The system...
There is a vent line going from the filler neck of the stainless tank to a small catch can under the trunk floor. Then a line from the catch can to the engine bay to a charcoal evap canister hidden under the fender. Then a line to the throttle body, drawing the fumes from the canister.
No valves to control the vacuum draw on the system. Pretty simple, but I just discovered a "T" in the vacuum line hiding under the brake vacuum booster, that can't be seen readily. So, there has been a 1/4" vacuum leak that the F.I. system has been compensating for all along! Also, it is drawing in unfiltered air, not a great idea.
A. I am wondering why the system was installed in the first place. The car was in Texas before I bought it...I could maybe understand if it was to be a California car, but I am unaware of any laws requiring such a system on a hot rod? Anybody else have such a system?
B. Should I leave the system operational, or abandon it? I am prone to leaving it (it ain't hurting anything, right?), but I am really bothered by the open vacuum leak, which I would think makes the actual draw on the system almost nil. (It can get all it's air draw from the open "T"). And it can't be helping the EFI system and the tuning of that.
C. If I plug the open "T", can/ will the vacuum cause fuel supply issues, and maybe even collapse the tank? That would suck (pardon the pun).

So I go back and forth, thinking of abandoning it, just plugging the vacuum line on the TB, and leaving it alone. I like the idea of capturing the fumes, eliminating fuel odors. And it seemed to work OK last year. Except I am really bothered by that vacuum leak! Do I plug that, or leave it?

Help please, this is really puzzling...and sorry for the long post.

Thanks!

Bill

[canrc]

Hey Bill -- what motor are you running?

[cmraman]

look into a II Much fuel vent

[69hugger]

Originally Posted by cmraman

look into a II Much fuel vent

There is already such a device, although not as attractive as the II Much piece. The hose you see is coming from the fuel tank. The picture doesn't show the hose coming out of the breather and going to the engine as described above.



It is the upstream part of the system I am puzzled by.



Thanks for the suggestion.

Bill

[JKnight]

I would think you could just eliminate the "T" with a two-way connector and that would eliminate your vacuum leak and keep the functioning system. It sounds like a robust system, but that someone forgot to go back and replace a T that they used during mockup. Just a theory...

[69hugger]

Thanks Jeff. That was my initial plan. Then a friend & I stared thinking about constant vacuum being applied to the fuel tank. As it has no other venting, I am fearful that could easily stall the car, or maybe even collapse the fuel tank. That negative pressure can be a powerful force.
AFAIK, the systems in our modern cars have a control valve to purge the charcoal canister at start up, then eliminate the vacuum during driving.

Anybody else have such a system?


Bill

[69hugger]

Originally Posted by canrc

Hey Bill -- what motor are you running?

It is a 534 c.i. BBC. .250" stroked 502.