I had the same issue when I drop below 1/4 tank at the final turn at Wakefield Park the 1st time out. I've not had the issue again since though, perhaps the coilovers helped to level the car more? Installing a surge tank would solve the issue, but then you have the issue of where to mount it. It cannot be mounted inside the car as it's a hatch, so it will need to be under the car. or you could install baffles around the fuel pickup inside the tank to prevent the fuel splashing around so much