02 Gtp crank no start timing off

Help! New build here 3800 SC with nitrous provision. Engine is completely new. Has a pcm tuned by intense. It acts like the timing is way off. Has fuel, spark at plugs, just seems spark is ill timed and possibly wrong cylinder. Everything is new, coils, plugs, wires, sensors, ignition module, etc. What am I getting wrong? I have hp tuners latest version but just got it and trying to learn. Old school engine guy here trying to figure this out. Your help is greatly appreciated.