Overfilling (Gas Topping) the 370z

POS VETT

I fill all the tanks to the brim on all of my cars for about a decade now. After normally filling a tank to the first click or normal container filling, I use a smaller 2-gal container (never through fuel pump nozzle unless the nozzle could go very slowly) to slowly and intermittently pour fuel in until the surface on the filler opening won't sink anymore; it's a very slow process and spilling must be kept to zero to minimum (usually a minor amount from splashing). For the hibernating cars, I may come back days or weeks later to top it off. I never had any problem with fuel vapor recovery system in any cars that I have owned or currently own.

Half a gallon is nothing. The additional amount that's "force-filled" varies from 2-4 gallons depending on the vehicle fuel tank, orientation of the vehicle while being filled, whether the vehicle is rocked, the amount of available fuel on hand, and lastly my patience.