Maserati Manual MK1
Mistral + 3500 GT Owner's Manual

(The "Bomb")

 Both engine-driven and electric motor-driven pumps have been developed for this purpose. The latter type has an
advantage in that it can be relatively small as a pump since, being independent of the engine, there will be adequate flow
available for cold starting under cranking conditions (requiring about 300% excess fuel for reasonably quick starting at
0° F.) and during warm-up which also requires excess fuel.
Most engine-driven pumps need an independent low pressure feed pump to maintain a continuous flow of fuel
through the pump to scavenge vapor away from the suction side, and this may result in installation complications in
some instances. With the motor-driven pump, all the pipe work from the fuel tank to the metering distributor is under
pressure as soon as the motor is switched on, effectively preventing the possibility of vapor lock.
Electrically, the pump is under the control of the ignition switch, while a thermal relay is provided to switch off
the pump after a short period should the car be left with the ignition on and the engine not running, thus preventing
unnecessary drain on the battery.