Originally Posted by
gerryndennis
I'm not quite sure how you figure that Sport. Let's use your example and put the tank 1/4 tank high, the floor of the tank is 1/4 tank below the needle, the roof is 3/4 above. Roll inverted and the 'floor' is now 3/4 below and the 'roof' 1/4 above. The fuel head varies by 1/2 the tank height wether it's a uniflow or standard tank. The amount of fuel in the tank is irrelevant.
Dave H
Because the vent is on a clunk the muffler pressure must overcome the head of the fuel. So the pressure at the pickup is always the same till the fuel level drops below the spraybar. That works if the fuel level drops or the tank position changes. So obviously there is some advantage to the uniflow setup till the tank is completely above or below the spraybar.