318 stumbles on full throttle

Just recently installed a new (stock)coil, plugs, wires, edelbrock intake, and 600cfm edelbrock carb on the fury's 318. Had the tranny rebuilt with shift kit installed. We took it out for a test run last night and it seemed to cut out on WOT. I set the timing at around 10-12*. I know it is past 10* because the stock timing tab will only show 10*. Lol. I set timing at 1000rpms. <<<<<<Could this be my problem from the start. I also removed the vacum advance and plugged the line to the carb to set initial timing. It seemed as later through the night we advanced the timing little by little and it seemed to get better. I dont want to go to far. B/c I am afraid something bad might happen. I dont know what main jets or metering rods are in the carb. It is brand new and dont have the manual in front of me to tell you. What else could be the issue and what advice can you guys give me to look at.

Thanks.

Chris
Author: 65fury