Anyone know what the fuel pump pressure should be for a 302 with mechanical diaphram pump?  

The typical engine mounted mechanical fuel pump will output from 5-7psi of fuel pressure depending upon brand, arm ratio, etc.

Any higher and you could force the needle off its seat and flood the carb with fuel. Rarely does a mechanical pump need a regulator...

You can purchase a simple vacuum/pressure gauge to check fuel pump output pressure.

HTH...
Mark  

Thanks Mark,

    Put a gauge on it last nite (I picked up a gauge at the shop,  what I thought was a 0-10 psi gauge turned out to be a 0-10 bar gauge,  so that was a bit useless).  Anyway, I had installed a new fuel pump and a new 4160 carb.  Fuel pouring out of the vent tubes.  Anyway,  turns out that Holley's claim that they are ready out of the box may not always be true.  Problem resolved with float adjustment.  (Of course this model did not have the exernal screws)

Regards

Mike  

Sorry to hear, but glad you got it worked out. Sometimes the floats stick of the carb is shelved upside down (even like on the UPS truck)...

I always give them a couple of raps with a screwdriver handle or rubber mallet on the float bowls once mounted to free them (just in case)...

Mark