Dan, In your other post concerning the need of more low end power for those short burst of speed. I was looking at the pic you have here on your oil leaking problem I saw your intake manifold and have a suggestion for you that could help you in your desire for more low end torque and hp. I think you are using the wrong manifold for what you are trying to achieve. Here is my suggestion from Edelbrock :

Performer #2131 (Idle - 5500 RPM)
Patented Dual-plane, low-rise design with a 180º firing order greatly improves torque over a wide rpm range for excellent throttle response from off-idle through 5500rpm. Performers are ideal for passenger cars, trucks, 4x4s and RV's.

While you are torn down this mite be the time to swap.

p.s. I would think that that 90* fitting on your intake would be for your vacuum to your power brake booster. Your pvc valve should go below your carb.