certain tanks also have another advantage of being fairly thin, being thin the weight of the fuel is more forceful on a smaller area of the tank (the bottom) where the fuel pickup is, on a flat tank the weight of the fuel is spread out more evenly and less on the fuel pickup, not many people realize it but every full sized car has the very same problem as we have with our glow engines, the reason why we cannot tell the difference with out full sized cars is that the fuel pumps can supply more then enough fuel to overcome the problem, it's only when you get to making big power that the stock fuel pumps cannot keep up with the demand the engine is putting on them and the engine starts running lean, it is an unavoidable part of fuel delivery in any vehicle that uses liquid fuels, the only way to get around it would be to use fuel jumps to pump the fuel to the carb instead of relying on the exhausts back pressure (which would actually be a very good idea because then we could get more power from our engines by getting rid of the very small exhaust stinger if we didnt need a battery to drive the pump.