I have been browsing the net, every now and then I come across toroidal fuel tanks.
http://www.go-lpg.co.uk/tanks.html
Has anyone ever encountered them? Do they have similar fittings as North American tanks? They appear to be the answer to conversion of smaller vehicles, such as a Honda Civic or a Toyota Corolla.
These tanks do not appear to have a vent line, will it be possible to get them filled in the USA?