I got issues!

Ok guy got my car finished but now im having issues. My motor is a stock bottom 318 with the following:
EQ heads
Summit .454 lift cam
Stage 2 mag springs
Gasket matched eddy performer intake
Street demon 625 carb
Double roller timing gearset
Stock manifolds
Factory electronic ign. (Non lean burn)

Cams broken in and i have the timing set at 34* at 3k rpms. Car starts and idles great, Free revs good, and drives good at a cruise. Whenever i try power braking and let off the throttle it tries to die, same as whenever i kick it down it tries to die and misses? Any ideas??