It is happening, Long Range America is building Fuel tanks for both Grenadiers

[anand]

They say on their website (or at least they used to) that they won't sell it in California. I'm not sure what makes it CARB non-compliant.

IIRC all aftermarket fuel tanks are illegal for sale in CA

 

[Brad@SuperiorCO]

The fact that they share the air volume - the factory EVAP setup is tuned to the size of a single tank.
That obscure tidbit is what made most Land Rover LS engine swaps illegal - a 1/2-ton GM's fuel tank is larger than most (old) Defenders'.

I believe everything else in LRA solution should be CARB-compliant, if they made fill openings capped separately. But the factory fill opening must use a factory (or a fully compatible) gas cap

I Have the LRA tank. At times, generally hot days, I do get a small fuel odor in my garage by my Gren when the garage door is closed. Unnoticeable otherwise. So I suspect that the stock EVAP really isn't sized for inclusion of the 2nd tank.

 

[pmatusov]

I Have the LRA tank. At times, generally hot days, I do get a small fuel odor in my garage by my Gren when the garage door is closed. Unnoticeable otherwise. So I suspect that the stock EVAP really isn't sized for inclusion of the 2nd tank.

Correct. Not that I personally care much, but it means anywhere in California that mandates visual inspection this setup would not pass.

 

[pmatusov]

IIRC all aftermarket fuel tanks are illegal for sale in CA

... among a million other things ...