Hey guys, what are your thoughts on this? I got all the parts and doesn't look too complicated to hook up. Will it do anything for my application? Image Unavailable, Please Login
I think you invented a new word there The main benefits are: 1. if you car goes upside-down, liquid fuel won't leak out, 2. it provides a way for air to enter the gas tank to prevent collapse as fuel is pumped out, 3. it provides a way for air to exit the gas tanks if a positive pressure develops inside the tank, 4. it does #3 without letting fuel vapors enter the atmosphere. At a minimum IMO (regardless of what you do), you need to have something in place that results in #1, #2, and #3. The "euro" set-up for your model will give #1, #2, and #3, but, IIRC, it has a different (extra) "nipple" set-up on the filler neck pipe (and I believe that they mangled the euro 308i-2V SPC for the fuel tanks as it shows the US RH fuel tank and no vent tube off the filler neck. See the euro 308QV SPC for how I believe the euro 308i-2V fuel tank system would be configured. Note the extra air vent tube coming off the filler neck that extends below the bottom of the tanks -- which puts the end of this tube above the liquid fuel level if the coachwork goes upside-down. If someone has an actual photo of a euro 308i-2V filler neck pipe showing the various tube connections, please post.)
Thanks for the explanation Steve. I'll hook it up then. The only issue I might have is #22, No plenum. Is that hose for air? (vacuum)
Yes, it should be connected to an intake air vacuum source -- this is used to "dry out" the charcoal bed inside the charcoal canister when the engine is running (so that it isn't saturated and can absorb fuel vapors if air+vapor comes out of the tank when the engine is off). If you don't have a common plenum area, and only hook it up to a single cylinder, then you need to make sure that when you "balance" the airflow entering into each cylinder that you (measure and then) account for this extra air entering the single cylinder (if you are using something like a Syncrometer that would not detect this additional air). The other option is to build a small tube network connecting #22 to all of the cylinders (as then, you can just assume that all 8 cylinders are getting an equal amount of unmeasured air and ignore it), but that looks a little messy.
I have this setup installed so it can work with a MAP sensor for my TBI. How about if I tap into that line in the last picture? Image Unavailable, Please Login Image Unavailable, Please Login
Maybe -- Essentially, you are adding a "leak" and those tubes are fairly small so that might be trouble (i.e., it might alter what the MAP sensor "sees"). If you hook it up there, and there is no change in what the MAP sensor reads = no problem. If you hook it up there, and the MAP sensor outout changes significantly = not so good.
I assume the euro setup vented to atmosphere. I'd have to suggest that for your application. For all the work you're putting into this thing to make it run right, you're going to be adding an unquantified flow path which will be contributing a varying hydrocarbon concentration with it, and relying on your O2 sensor(s) to compensate for it. Run the tank vent system to atmosphere and plant a tree to save the planet.
