With a modified motor that has a cam, intake, carb and headers you need a better timing curve.
Read this.
http://www.badasscars.com/index.cfm/...d=76/prd76.htm
Your 8 initial is likely half of what you need.
I run stock motors at 14 initial here at sea level.
Eddy carbs and their ancestors (the afb) never like more than 5 psi. Don't worry, you won't run out of fuel. I ran a pair on a dual quad that had 2 psi at wot at 120 mph and never ran out of fuel.
Where in Alabama do you live?
Your elevation and ambient temperature effect how your motor runs.