(quick slide back into thread -- :_paranoid )

Marty, I can't answer about a custom tank. I'd guess that a factory tank and its 5/16 or 3/8 supply line would be just fine, along with a vented cap. I'll bet that such an arrangement does have a gas smell in the garage though.

There's a reason why you don't see gas tank filler necks at knee level anymore. They are a pain in the ass to fill, AND they are a bitch to vent. I played hell with mine like everybody else. As was said, that whole loop deal doesn't work. It just makes the tank belch and does a poor job of venting. A canister in the trunk and back out to fresh air is the only way I made mine not spill gas even at full tank. You could get all factory and put a pressure sensor/solenoid into a charcoal canister. To much work for me. I agree, Rick should really know how to vent his own tanks. A proper fuel level sensor would be nice as well. :unibrow: That being said, my tank has been good to me. You just need to tweak it in like many other things.

For what it is worth, I installed a plastic tank from a 96 Caprice in my 69 Camaro - with some mods.

It has a factory vent line that I attached to a charcol can set up from a late model GM 1500 pick up. Since the car is fuel injected with the LS and return line...the LS computer also had the output and my Painless Harness had the purge line connections. No brainer - hooked them up and put a sealed cap.

Long story short - no odor, no leaks, no issues - it acts totally OEM.

I also did a 69 Corvette a few years ago with a stock 69 tank - I used an early 90s full size Chevy truck charcol can and mounted it next to the tank. I ran the vent to it - and no vacuum from the engine. I ran a sealed cap and had no odor or drip issues.

I know that is a bit off topic, but I do think if you have a larger vent line - then run it through a OEM charcol and in the best case hook to the PCM through the valve....your drips and odors will be gone.

I'm not saying the caprice mod is easy - but it was very inexpensive and allowed use of multiple OEM parts including OEM quick fit lines...etc and proper vent tubing.

http://mcspeed.homestead.com/files/c...k_complete.jpg

^That turned out pretty good, but this thread is about a problem with high dollar aftermarket tanks ,we all know that we can adapt OEM charcoal canisters or whole venting system off some other late model car, but I think these tanks should come with nicely packaged venting system that works and doesn't stink up the car or garage

Agreed - I just figure you can't go wrong applying an OEM technique to these tanks to bring them into a proper working order.

I know sometimes we get so far out with modifications that we have to make modifications to cover our modifications...and eventually come back to the way the folks that designed these things with the benefit of years of test tracks and other R&D did it.

I would have never guessed the custom tanks would have this problem. You figure a tank is a tank and a vent is a vent.

You got me rolling, this is so true, sometimes:rofl::rofl: :rofl: :rofl:

Agreed. I never would have guessed that the top dollar tanks still have such a basic problem. I'm also surprised LS1 conversions have been around for so long and there's never been a thread about this until now. :wow:

could you expand a little. im not up to date on how all of these work. it sounds like the factory solutions may be pretty simple but im not completely following.

my previous thought was to do as pictured above with a very small tank (~1 qt) mounted up higher than the main tank. i would then have two main tank vents plumbed into the smaller vent tank; one line plumbed into the bottom from the filler neck and one into the bottom from the main tank. this small tank would then be vented out the top.

If you have any older Chiltons or other repair manuals for older cars, take a look at the emissions section. You should be able to find a simple diagram of how the lines are connected in a vapor recovery system with a charcoal canister.
The systems are really simple in how they work. Building one at home from OEM parts should be really easy for you after everything you have done on your project yourself.

If you build one please post pics.

If you look under the hood of a 1988 to about 1997 or so Chevy truck you will see a coffee can canister behind the left front headlight. It has a couple of lines on it. One is the vent coming from the gas tank. Another goes to the intake - and I can't remember where the third one goes. Anyway, on my 69 Vette aka Killer - I used one of these and hooked the vent line from the tank to the can. The can acts like a big air filter that not only allows pressure to come off the tank and get scrubbed to remove the gas odor, but it also allows the tank to breath in through the valve on the top of the unit. I like what 70rs says about looking at the Chilton diagram and just hooking it up.

On my LS set up, I simply duplicated the vacuum lines off the 1996 Caprice tank to a 2002 or so style full size truck charcoal can. These are square shaped and are found on the driver side under the bed behind the cab. You can get them from the bone yard cheap or nearly free. Nobody really wants them for anything. They have a valve you have to get that will hook to your LS wire harness for the purge. You will want to run the vacuum line back up to the engine just at the LS does from the factory. I was able to tuck the unit on the right frame rail by the tank on the Camaro.

I see no reason why you couldn't hook one of these up to a Ricks or other tank - as long as the vent on the tank is sufficient to begin with.

The 68 Firebird we are building right now has a stock tank and stock vented cap. Man...I had forgotten what a pain the gas vapors can be. We were out there working last night - Camaro and Firebird side by side in the shop. When the sun sets and the garage door is open that heats the rear of the cars and you really pick up some odor out of the Firebird - the Camaro is just like a new car - no odor at all...facing the same exact circumstances.

It is worth looking into.