Originally Posted by wstar

On the stock system the pump is in the passenger (right) side, and yes there's a simple crossover tube to the left (driver) side that tries to slowly level out the two. When you take a long hard right-hander, all the fuel goes to the left (driver) side, away from the pump, and that little crossover balancing tube really can't do anything about that. It will slowly level the two sides when there's no significant side load on the car, but it can't go against the g-force (or supply enough fuel to keep the pump running regardless).

Even after having seen it up close and installed it (twice!), I still don't fully understand Phunk's system, but it's complicated and it seems to work in all conditions, so I don't care how it works as long as it works

It puts a surge can and secondary pump in the driver's side, and runs 3 hoses back and forth between that and the factory pump on the passenger's side, and also involves some modifications to the internal hoses on the factory pump module (which also has a very small reservoir area). Others have backyard-engineered other systems with other tradeoffs (including pumps with pickups in the all the corners of the tank, cutting the tank in half so there's nowhere to hide the fuel from the pump at, etc. I'm sure you can make something else work cheaply if you want, but there's always tradeoffs...