Don and Jim---The stock fuel pump puts out a maximum pressure of two
lbs., no matter the rpm. (Some may see 2 1/2 lb.)
An electric pump with a regulator may be necessary under racing
conditions, if the rest of the engine is built for thirst.
Most (all?) Webers have an accelerator pump or power valve, that squirts
fuel when you pump the gas pedal, which helps to start a cold engine.
Since Constant Depression carbs do not have these, it's necessary to
enrichen the mix by "choking" off the air, or lowering the jet. Either
option allows for easier starting.
Dick Taylor
'73
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