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OLDFLM
07-20-2015, 05:15 AM
The "standpipe" in my Firebird is long gone but like many who are still running a traditional V8 with a carb, I've been dealing with increased gas fumes in the garage with modern fuels these past few years... and it seems to be getting worse with the hotter days of summer so I'm trying to figure out a cure. Then I figured the GM engineers already did that and I just need to locate another standpipe to put back behind the back seat.

Anybody have one laying around by chance?

My research has raised a few questions:

A) My EEC replacement tank has all the vent tubes capped and I've been running a vented cap... could this be contributing to my stalling issues and vapor lock like symptoms? Possibly the tank isn't getting enough air for the fuel demands?

B) IF I can source another standpipe... can I simply run the three vent lines from the tank to the standpipe and then run the fourth line from the standpipe (that used to go up front to the charcoal canister) to open air or through a small filter to keep dirt out but still allow it to vent? Something small that could be easily mounted near the tank like the NAPA 33321/Wix 3321 or even just a small crankcase filter?

C) If I do "B" will I still need to run that fourth line to some sort of charcoal EVAP canister to rid the garage of fumes and the smell? Jeeps and BMW charcoal canisters seem to come up most often on internet searches... has anyone found a better solution? There's got to be a small, easily mountable modern charcoal canister that would fit back there.

D) What cars came with the standpipe behind the backseat? And what did they do before/after the standpipe to vent the tank? I know some Firebirds and Camaros had them, but others didn't... 71/72 Firebirds had them but not later 'birds like the 75 nor earlier Camaros like the 70. A buddy said his Olds 442 has one too.

I've searched on here and on the web and this newer fuel seems be causing a lot of vapors/gas smells and vapor-lock issues. On hot days the fuel vapors in the garage are strong enough to be alarming... and are probably dangerous if any kind of spark could ignite them!

Thoughts? WWPTD?

Regards,

Ty

dhutton
07-20-2015, 06:39 AM
What about simply adding a IIMuch fuel tank vent?

Don

OLDFLM
07-20-2015, 06:48 AM
I've looked at them but I'm thinking I need to find another standpipe... then run the three vents from the tank to the standpipe as an "expansion tank" and then run the 4th line from the standpipe to a charcoal canister. I'm not sure if the IIMuch fuel vents have activated charcoal in them (or need it?) or if they simply act as an expansion tank for the vapors to collect in and then vent to open air? What happens to the liquid fuel that condenses and collects? Does it return to the tank through the feed line?

parsonsj
07-20-2015, 06:57 AM
Ty, I'm no longer directly affiliated with the II Much vents (I sold the business), but one II Much vent properly connected will work great in your application.

Give them a call at 888-216-6033.

OLDFLM
07-20-2015, 07:15 AM
Thanks JP! So no need for the standpipe or an expansion tank? Just run all three tank vents to one II Much vent?

parsonsj
07-20-2015, 08:11 AM
In a nutshell, yes. I'd connect one to a II Much vent, and plug the other two.

OLDFLM
07-20-2015, 08:24 AM
Okay, that's a LOT simpler than what I'd imagined! The middle vent on these EEC tanks is 3/8" and was the return line for the standpipes, so I'll cap the outter two (left and right) on the gas tank and run the center vent off the tank to a II Much vent. Thanks again JP!

https://static1.pt-content.com/images/pt/2015/07/standpipe_zpsmp9y7wbi-1.jpg (http://s691.photobucket.com/user/OLDFLM/media/standpipe_zpsmp9y7wbi.jpg.html)