holley (mechanical)750 dbbl pumper

[torque455]

this might be a dumb question..but when i have car in park and was adjusting idle a mixture scews i noticed the squirter in the back isnt squirting if i rev up the motor ...does the back one work under load or at what time does this start to pump fuel?

 

[85 Cutlass Brougham]

What carb? For anything but a Holley double pumper, the secondary squirter should not do anything unless it is under load at WOT. It technically isn't really a squirter on those carbs, but rather the booster venturi enrichment thingie.