Opel Rallier since 1977
FWIW, the reason I used a backup pump is it was racing.... rally. Hard use.... no need to DNF due to a stupid failure. Never have run a back-up on the street. Just avoid the Facet 'cube' type pumps IMHO.... noisy and failure prone.
The Facet 40178 Cube 12 Volt Fuel Pump delivers maximum flow of 15 GPH or 2-3.5 psi max pressure. 1/8 NPT female ports. Kohler numbers 249862/278490.