The fuel system is a no return system. I would have still tried it with a return system I just would have run it with half a tank or less for expansion. I have multiple experiments going on with fuel at the same time. And as long as I see increases in MPG I will keep at it. When it all levels out and I can't get anymore MPG I will start testing individual systems. Right now they are all working together and I have gains in MPG. This is a lot of fun for me and of course the benefit of saving ga$$$ and building, bullet proof systems.
