Hi folks, it's been a while!

I just got done building and installing my 355 in my '70 Nova, and I'm having some carburetor problems here.

The motor idles great, makes awesome vacuum and oil pressure, but I have a problem. I think it's getting way too much gas. On anything other than a slight acceleration, I get a tremendous bog (sometimes resulting in a backfire, and if from a dead stop, killing the motor!). I am using a Edelbrock 1405 carburetor and a Holley HP Mechanical fuel pump.

I thought that it could have been one of the following:

1) Too high of fuel pressure. I'm using a high performance holley pump, and I know the carb wants 5.5 lbs at idle, haven't been able to aquire a guage to check this.

2) Bad accellerator pump diaphragm? I don't know much about carburetors, so I couldn't say.

Here are the specs of the motor:
350 + .030 one-piece rear main seal block
Dart 185cc intake runner 72cc chamber heads
Small street split pattern cam
Accell blueprint distributor
MSD Blaster SS Coil
Edelbrock RPM Air Gap intake
3000 Stall

Any ideas? It's sad not being able to romp on the motor now that it's broken in, and if this is excessive fuel, I don't want to wash my cylinder walls here.