Walbro F90000267 450LPH pump is the highest flowing intank fuel pump on the market, and is E85 safe to boot. Walbro designed the pump to meet the requirements of modern turbocharged applications where a single 255LPH fuel pump is insufficient. The pump uses a turbine style design which incorporates two composite plastic blades. The turbine design lends itself to extremely quiet operation, especially compared to Walbro's previous "gerator" pump design that had metal gears which were notorious for a very loud whining noise which could easily be heard over even the loudest aftermarket exhaust setups.
The Walbro 450LPH pump can flow anywhere from 15-120psi (the bypass valve is set higher than Walbro's previous fuel pumps, which were around 85psi). Final fuel pressure is determined by your fuel pressure regulator. Please note that this is an aftermarket fuel pump, and some modifications may be required to get it to fit.