Bosch make a pump which fits into the tank. I am not sure if this will flow for 550 bhp but if it won't I think the only way to get round it is use this pump to lift the fuel into a swirl/collector pot then 2 pumps to supply the fuel down -6 fuel lines. You will probably also need to uprate the pump wiring as well.

You will need to confirm but I think the Bosch in tank pump is 0 580 254 003.