As usual, a fellow DML'er handed me an epiphany, well sort of...something I had been considering but didn't want to admit. Consider: An engine with new head gaskets that had the timing chains and sprockets removed, now assembled cranks exceedingly hard. New starter, new, larger capacity battery. Timing light indicates 13 BTDC. That's only electrical timing though. I am absolutely certain that the pistons have not struck and bent any valves (engine was handcranked first) but could I still be off on my valve timing? If the valves weren't synchronized properly, then the engine is fighting itself right? It has also occurred to me that I don't here any of the "sighing" that the air makes when expelled or inhaled. I don't know about the PRV but I'm used to this in other engines. Help me with valve timing terminology: What does "on the rock" and what does "overlap position" mean when referring to the valve positions? Open, closed or what? I have everything else. Fuel, air, good, hot spark. Starting fluid changes nothing. New fuel pump, CPR, injectors, fuel dizzy, filter. All tested sat. What else could it be besides timing, given the symptoms? Thanks, Rich #5335(The Zombie DeLorean)